Bikeradar's relatively thorough study on wheel size comparison.- Mtbr.com
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  1. #1
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    Bikeradar's relatively thorough study on wheel size comparison.

    29'er fastest overall, 26'er fastest on decents. 27.5 slowest overall. Sometimes what geometry tells us doesn't always translate into something better. The leader of the study almost seemed uncomfortable revealing that the 650b is just hype.

    Keep in mind that they did not have all of the proper controls in this study and that the riders did not have extensive experience riding 27.5 bikes so maybe some conformational biases.

    https://www.youtube.com/watch?v=kxfrykeSNCE

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    Not surprised to see an XC course coming out with 29ers faster.

    A little hard to parse what Hurst was saying, but my interpretation was that all the data they logged found no differences between the 3 options. The only significant findings were from the stopwatch.

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    Oh wow, a wheel size debate, must be one of those days ending in Y.
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    Quote Originally Posted by kyle242gt View Post
    Oh wow, a wheel size debate, must be one of those days ending in Y.
    Yet, you were still compelled to chime in....

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    Yeah, but did they account for FUN? Which wheel is "funnest" to ride....?

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    Quote Originally Posted by mhopton View Post
    Yeah, but did they account for FUN? Which wheel is "funnest" to ride....?
    he said "26'er fastest on decents" duh

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    All that test really tells me is that Santa Cruz's Superlight 29er is faster than the Superlight 26 or 27. The terrain they were riding looked pretty tame IMHO. How would a different brand and pivot design like DW link compare. Well you can't really because it changes some many ride quality factors.

    Personally I think 650b shines in the new all mountain/ trail/ enduro category where you are looking at slacker HT and 150mm + suspension. Fast? I don't really care, I don't race. Also most of these bikes you aren't going to be winning any races to the top. Downhill? Well the pros certainly don't seem to have any issue with the 650b, but they can kill it on any bike right? What was the point again?
    Sent via my heady vibes from the heart of Pisgahstan

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    I am confused why he says that the data analysis shows no difference, but then they have massive real-world differences in lap times during this test.

    We do know that 29ers have less rolling resistance and there is slightly less deflection going over / through small objects due to the diameter. Bike Radar and the scientists did not have any explanation for the 27.5 real-world performance.

    Despite riding a 26 and having more than a healthy suspicion about 27.5 being an 'upgrade', I just can't get my head around 27.5 being significantly slower than 26. It should be the same, because the tire is only 4.5% larger (ETRTO).


    One thought that follows from this-- if you're upgrading from 26" to 27.5 you probably better get a different bike, better fork, or something like that. Because, shockingly, they aren't very different on identical bikes.

  9. #9
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    ill say it again...

    29ers = big boats
    27.5 = aint much different from 26ers

    26ers aint dead! mine rips!

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    Quote Originally Posted by ColinL View Post
    I am confused why he says that the data analysis shows no difference, but then they have massive real-world differences in lap times during this test.
    I interpreted him as meaning the data they logged from all those sensors (the mask, the things mounted to their skin, accelerometers and whatnot on the bike) came out with no statistical difference, but the stopwatch showed that everyone finished laps faster on average when riding the 29ers compared to the other wheel sizes.

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    If I remember correctly it was 3 riders doing 1 lap per bike. With times around 15minutes a 20 second difference is a whooping 2% difference. I'm not a statistician but this seems like it could easily be in the margin of error. Especially when none of the riders had experience on the bike that was the slowest at everything, I don't think that's negligible. Hell on a 15minute segment on the exact same bike that I have ridden for multiple years a lot of my times dont fall within 20 seconds of each other.

    They should have saved the money from the **** ton of sensors and used it to test it multiple times over the course of a week.

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    Quote Originally Posted by nauc View Post
    he said "26'er fastest on decents" duh
    Somebody better tell that to all the DH and Enduro racers.

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    Quote Originally Posted by rockdude14 View Post
    If I remember correctly it was 3 riders doing 1 lap per bike. With times around 15minutes a 20 second difference is a whooping 2% difference. I'm not a statistician but this seems like it could easily be in the margin of error. Especially when none of the riders had experience on the bike that was the slowest at everything, I don't think that's negligible. Hell on a 15minute segment on the exact same bike that I have ridden for multiple years a lot of my times dont fall within 20 seconds of each other.

    They should have saved the money from the **** ton of sensors and used it to test it multiple times over the course of a week.
    Absolutely agree. Each bike benefits from a particular riding style, and the margin of error there is huge. I'm not a big fan of 29ers for my riding, but there is no way the smallest wheelsize would roll the fastest down a hill. That's really where a bulldozer of a wheelsize should excel.

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    Did i hear something in there about it being down to the rider.

    You heard the man 26ers ain't dead

    Anyone want to buy my 26er?

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    A 20 second/2% diff is very significant if it represents a real increase. I know in my races I would have gladly had a 2% increase it is the difference between podium and top 10. That's true for most of my classes whether its a 3 minute dh run or a 25 minute TT or a 2 hour XC race, 2% is huge. That being said I agree with the rest of your statement, if you ask me to go do a 15 minute fast lap, my 2nd and 3rd laps will be significantly slower. Doesn't seem like a valid test.

    >29ers = big boats

    >everyone finished laps faster on average when riding the 29ers

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    right, but if it's only rolling diameter, why did the 27.5 lose to 26?

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    Quote Originally Posted by nauc View Post
    ill say it again...

    29ers = big boats
    27.5 = aint much different from 26ers

    26ers aint dead! mine rips!
    The 26" GT Avalanche Expert is now a 27.5".......by definition it is dead :-)

    My son's 26" SC Nomad serves him very well! :-)

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    Quote Originally Posted by ColinL View Post
    right, but if it's only rolling diameter, why did the 27.5 lose to 26?
    This was a surprise to me too and my guess is bad testing methodology. Maybe they did 27.5 first and the riders were warming up or still learning the course, maybe they did it last and they were most tired, maybe they just weren't use to a 27.5 and were playing around and seeing how it performed and not going all out since they said none of them had experience with it.

    While this might also be a good test for XC this looks really tame compared to most of what my riding looks like. I really wish they had a steeper and rougher course too.

    Anyone know if they actually list all the lap times they recorded? Might be able to do a little statistics and see standard deviation or confidence interval.

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    Quote Originally Posted by rockdude14 View Post
    Anyone know if they actually list all the lap times they recorded? Might be able to do a little statistics and see standard deviation or confidence interval.
    If you check out part 1 it's pretty clear that BikeRadar is stopping by to check out a study being conducted by Dr. Hurst. Part 1:
    https://www.youtube.com/watch?v=vhS1HfvBeYA

    So, I'd imagine he's got the data and has grad students or post docs who will present or publish it. I found him at UCLan here:
    Howard Hurst | Staff Profile | University of Central Lancashire

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    Huh. Hurst comments on the video if you scroll down. Which surprises me -- a researcher taking the time to reply to YouTube comments? Really? -- but anyway, here's what he posted:

    Quote Originally Posted by Howard Hurst
    Fair comment. I did say that it is largely a matter of choice and what you feel comfortable on. We just didn't see any correlation between height and wheel size and performance in the sample we tested and they were quite diverse in height. You will always get some tall riders who feel comfortable on smaller bikes and some smaller riders feeling better on bigger bikes. That's nature I guess.

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    Maybe, just maybe 27.5" is not the best of both wheel sizes, but instead the worst. Maybe the emphasis is not that the 27.5" rolls better than a 26" and is more maneuverable than a 29er, but instead the emphasis is that the 27.5" does not roll as well as a 29er and is not maneuverable as a 26".

    Quote Originally Posted by mountainbiker24 View Post
    Absolutely agree. Each bike benefits from a particular riding style, and the margin of error there is huge. I'm not a big fan of 29ers for my riding, but there is no way the smallest wheelsize would roll the fastest down a hill. That's really where a bulldozer of a wheelsize should excel.
    Quote Originally Posted by ColinL View Post
    right, but if it's only rolling diameter, why did the 27.5 lose to 26?
    There is a lot more to mountain biking than just how well a particular wheel size bulldozes a trail. If you were able to ride a bike like you drive a car then how well the wheel rolls would be a bigger deal. However, unlike a car bikes are independent from the rider and can be thrown around, bunny hoped over obstacles and maneuvered to be in the best position relative to the rider to take a corner faster or tackle an obstacle quicker than simply just plowing through it.

    The 26" is more maneuverable and quicker to react to the rider. At faster speeds, like going down hill, this matters even more as the rider will be faster at getting the bike into the best position allowing it to take a corner or get over an obstacle faster than the 27.5" or the 29er.

    The 27.5" only has a 1/2" more rollover than a 26" which is not very significant, but for that 1/2"inch you loose maneuverability from quite a few different areas. That small amount of extra rollover increases the wheel base and chain stay, increases the BB drop, raises the stack by 1 inch and increases the rotational weight of the wheels, not just because the 27.5" wheels are heavier, but because the majority of the weight is further out from the axle as well.

    While the 29er also reduces the maneuverability even more in the same areas, unlike the 27.5", the 29er has a significant amount of increased rollover compared to the 26". In fact it has 150% more rollover over the 26" than the 27.5" has over the 26". So while the 29er looses maneuverability compared to the 26", it gains a significant advantage in rollover, while the 27.5" only gains a marginal advantage in rollover for its loss in maneuverability.

    Also, on top of all that the 26" is able to get back up to speed quicker than a 27.5" while the 29er rolls faster than the 27.5".

    So the 27.5" is slower to accelerate, is not as maneuverable and rolls just slightly faster than a 26" and it doesn't roll as fast as or "bulldoze" over objects as well as a 29er.

    The results of this study make perfect sense to me and is why I sold my 27.5", but kept my 26" and 29er. I bought the 27.5" over 2 years ago thinking it would replace my 26" and 29er, but instead I found myself riding the 29er on xc and fast flowy trails and my 26" on technical black diamond trail rides while the 27.5" collected dust in the garage.

  22. #22
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    Quote Originally Posted by tahoebeau View Post
    Maybe, just maybe 27.5" is not the best of both wheel sizes, but instead the worst. Maybe the emphasis is not that the 27.5" rolls better than a 26" and is more maneuverable than a 29er, but instead the emphasis is that the 27.5" does not roll as well as a 29er and is not maneuverable as a 26".
    This was undoubtedly my experience with 650B. I've owned six or seven of them and just didn't see what the big deal was/is. But I'm more of a 29er guy. All of which is not to say it's a bad wheel size. If you dig it, that's all that matters.

  23. #23
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    So their conclusion was that it's the rider, not the bike? **Cough-beensayingthatforovertwodecades-Cough**. Moving on...
    I only ride loam:)

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    To me this course seems far from an ideal testing ground for the three wheels sizes. If I rode those conditions I'd be riding a 29er too.
    I would love to see the results over a more (I hate to say it) enduro type course, or something representing more all-mountain like I ride.
    Also I really don't care about fastest. I don't race at all. To me one things matters: fun. And in that regard 650b/27.5 has been a hands-down winner.
    I really don't get people who say there's little difference over 26 or don't feel it riding. If it's not for you that's one thing, it's so personal. Don't don't feel a difference? No way.
    It was instantly noticeable to be when I switched from 26. Literally the first seconds on the trail.
    While it's not huge, that increase in tire size and wheelbase makes a very big difference in rollover and stability and confidence yet maintains all the fun of 26.

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    I've tested 3 650b bikes. All felt slightly more awkward than 26 with nowhere near the freight train speed of 29.

    Before the slanted 650b marketing blitz pinkbike did an objective comparison and 650 came in last too.

    I wish Specialized had the sack to stick to their guns when they said 27.5 was unnecessary.

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    Quote Originally Posted by tahoebeau View Post
    Maybe, just maybe 27.5" is not the best of both wheel sizes, but instead the worst. Maybe the emphasis is not that the 27.5" rolls better than a 26" and is more maneuverable than a 29er, but instead the emphasis is that the 27.5" does not roll as well as a 29er and is not maneuverable as a 26".
    If I could ride two bikes at the same time, I would certainly choose to ride a 26er and a 29er. But I can't. In fact, I only am willing to own 1 MTB. So for me, I think 27.5 is a glass half full kind of thing.

    Edit: but really, it didn't matter since in ABQ when I was shopping for a bike there were no slack 26ers in any of the LBS so there wasn't really a choice. I went with the bike that felt the best on test rides, which happened to be a 27.5. I like it
    It's just a flesh wound!

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    Quote Originally Posted by IPunchCholla View Post
    If I could ride two bikes at the same time, I would certainly choose to ride a 26er and a 29er. But I can't. In fact, I only am willing to own 1 MTB. So for me, I think 27.5 is a glass half full kind of thing.
    That's well said.
    I too only own one bike and find the 650b a perfect, blast to ride, do-it-all bike.
    I would only change one thing about your comment: I think 27.5 is more of a glass almost full kind of thing

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    I like how the small diameter difference of 27.5 means nothing when it comes to rollover, but it makes a huge difference when it comes to maneuverability, and that 2-3oz weight difference means everything as well.

    MBA did a test a few years ago and the 27.5 came out on top...and pro racers seem to agree. They might run what they're given, but if they aren't doing whatever they can to win, race teams aren't doing their jobs.

  29. #29
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    Quote Originally Posted by richde View Post
    I like how the small diameter difference of 27.5 means nothing when it comes to rollover, but it makes a huge difference when it comes to maneuverability, and that 2-3oz weight difference means everything as well.
    Exactly.

    Silly test and conclusions IMO.

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    Quote Originally Posted by richde View Post
    I like how the small diameter difference of 27.5 means nothing when it comes to rollover, but it makes a huge difference when it comes to maneuverability, and that 2-3oz weight difference means everything as well.
    If it was just the extra weight of the larger wheels that effected maneuverability then it probably wouldn't matter that much, but it could be the combination of extra rotational weight, longer chain stay, longer wheel base, larger BB drop, and higher stack all combined together that negatively effects maneuverability more than what you gain with the 1/2" more in rollover.

    But ultimately I don't think there is a significant difference in performance between the 26 and 27.5 wheel sizes. This study shows that the 26" is slightly faster than the 27.5", but not by much. However that does beg the question, if there is not a significant difference and if anything the 26" does perform slightly better, then why 27.5"?

  31. #31
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    Bikeradar's relatively thorough study on wheel size comparison.

    Quote Originally Posted by tahoebeau View Post
    If it was just the extra weight of the larger wheels that effected maneuverability then it probably wouldn't matter that much, but it could be the combination of extra rotational weight, longer chain stay, longer wheel base, larger BB drop, and higher stack all combined together that negatively effects maneuverability more than what you gain with the 1/2" more in rollover.

    But ultimately I don't think there is a significant difference in performance between the 26 and 27.5 wheel sizes. This study shows that the 26" is slightly faster than the 27.5", but not by much. However that does beg the question, if there is not a significant difference and if anything the 26" does perform slightly better, then why 27.5"?
    It very much begs the question. It's not as if, despite what many want to believe, the manufacturers were the ones pushing 27.5 and sticking with only 26 and 29 for racing.

    All I know is that on my first demo ride on a 27.5 I could feel a difference in rollover. It was slightly less nimble, but that was simply a timing issue that I felt could be easily overcome as soon as I got a few rides in. Turns out that after getting one, I was right...and my Strava times reflect how much easier it is to ride quickly on it.

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    Soon everybody is going to be looking for ways to convert their 27.5 bikes to 26". Mark my words.

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    Quote Originally Posted by richde View Post
    I like how the small diameter difference of 27.5 means nothing when it comes to rollover, but it makes a huge difference when it comes to maneuverability, and that 2-3oz weight difference means everything as well.

    MBA did a test a few years ago and the 27.5 came out on top...and pro racers seem to agree. They might run what they're given, but if they aren't doing whatever they can to win, race teams aren't doing their jobs.
    It would make sense that teams would go with equipment that offers the best chances to win, but what doesn't add up is 26 took 1st and 2nd in the EWS last year and was leading the overall this year before being removed from competition? Not sure why any company would say we need to ditch 26 for 27.5 with such results. If anything you would think companies would reevaluate moving away from a wheel size that dominated the podium in the discipline where 27.5 was supposed to shine brightest.

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    Quote Originally Posted by tahoebeau View Post
    Maybe, just maybe 27.5" is not the best of both wheel sizes, but instead the worst. Maybe the emphasis is not that the 27.5" rolls better than a 26" and is more maneuverable than a 29er, but instead the emphasis is that the 27.5" does not roll as well as a 29er and is not maneuverable as a 26".





    There is a lot more to mountain biking than just how well a particular wheel size bulldozes a trail. If you were able to ride a bike like you drive a car then how well the wheel rolls would be a bigger deal. However, unlike a car bikes are independent from the rider and can be thrown around, bunny hoped over obstacles and maneuvered to be in the best position relative to the rider to take a corner faster or tackle an obstacle quicker than simply just plowing through it.

    The 26" is more maneuverable and quicker to react to the rider. At faster speeds, like going down hill, this matters even more as the rider will be faster at getting the bike into the best position allowing it to take a corner or get over an obstacle faster than the 27.5" or the 29er.

    The 27.5" only has a 1/2" more rollover than a 26" which is not very significant, but for that 1/2"inch you loose maneuverability from quite a few different areas. That small amount of extra rollover increases the wheel base and chain stay, increases the BB drop, raises the stack by 1 inch and increases the rotational weight of the wheels, not just because the 27.5" wheels are heavier, but because the majority of the weight is further out from the axle as well.

    While the 29er also reduces the maneuverability even more in the same areas, unlike the 27.5", the 29er has a significant amount of increased rollover compared to the 26". In fact it has 150% more rollover over the 26" than the 27.5" has over the 26". So while the 29er looses maneuverability compared to the 26", it gains a significant advantage in rollover, while the 27.5" only gains a marginal advantage in rollover for its loss in maneuverability.

    Also, on top of all that the 26" is able to get back up to speed quicker than a 27.5" while the 29er rolls faster than the 27.5".

    So the 27.5" is slower to accelerate, is not as maneuverable and rolls just slightly faster than a 26" and it doesn't roll as fast as or "bulldoze" over objects as well as a 29er.

    The results of this study make perfect sense to me and is why I sold my 27.5", but kept my 26" and 29er. I bought the 27.5" over 2 years ago thinking it would replace my 26" and 29er, but instead I found myself riding the 29er on xc and fast flowy trails and my 26" on technical black diamond trail rides while the 27.5" collected dust in the garage.
    I find my 650b to be the best all-around wheelsize for me. My 29er rolls and maintains speed better than my 650b and old 26ers, but isn't as much fun to ride. My old 26ers were fine, but not as good as my 650b. That's all I care about. I couldn't care less about your opinion. I do believe that wheelsize had less impact on the test results than the testers' riding styles and comfort levels. As far as bulldozing goes, well, rolling over irregularities will maintain momentum and should be faster with equal effort.

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    Bikeradar's relatively thorough study on wheel size comparison.

    Quote Originally Posted by slimat99 View Post
    It would make sense that teams would go with equipment that offers the best chances to win, but what doesn't add up is 26 took 1st and 2nd in the EWS last year and was leading the overall this year before being removed from competition? Not sure why any company would say we need to ditch 26 for 27.5 with such results. If anything you would think companies would reevaluate moving away from a wheel size that dominated the podium in the discipline where 27.5 was supposed to shine brightest.
    Graves didn't run a 26 all season long, neither did Anne-Caroline, and none of the teams that ran 26 did it while there was a 27.5 option available. As soon as one became available, even though they weren't available to the public, the racers swapped over.

    Downhillers did the same thing.

    It really is more the rider than the bike in most cases, but at the same time, they're not going to skip on taking an advantage when it's available.

    Keep in mind that Yeti already had a 26 with Enduro geometry (same with DH bikes/teams), so making the huge investment in new molds for a new carbon frame is no small matter.

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    Quote Originally Posted by richde View Post
    Graves didn't run a 26 all season long, neither did Anne-Caroline, and none of the teams that ran 26 did it while there was a 27.5 option available. As soon as one became available, even though they weren't available to the public, the racers swapped over.

    Downhillers did the same thing.

    It really is more the rider than the bike in most cases, but at the same time, they're not going to skip on taking an advantage when it's available.
    Graves won the ews in Valloire in June on the sb66 after it had already been discontinued. He had a 27.5" option available, but chose to ride the discontinued 26" while almost everyone else riding 27.5" and 29ers Guess he felt the advantage was with the 26". However, like you said, it's really more the rider than the bike and Graves is a bad a$$. But regardless you gotta ride what your sponsor sells and I'm sure Yeti didn't want him riding too many races on a discontinued bike model.

    WINNING BIKE: Jared Graves' Yeti SB66c - WINNING BIKE: Jared Graves' Yeti SB66c - Mountain Biking Pictures - Vital MTB

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    Bikeradar's relatively thorough study on wheel size comparison.

    Quote Originally Posted by tahoebeau View Post
    Graves won the ews in Valloire in June on the sb66 after it had already been discontinued. He had a 27.5" option available, but chose to ride the discontinued 26" while almost everyone else riding 27.5" and 29ers Guess he felt the advantage was with the 26". However, like you said, it's really more the rider than the bike and Graves is a bad a$$. But regardless you gotta ride what your sponsor sells and I'm sure Yeti didn't want him riding too many races on a discontinued bike model.

    WINNING BIKE: Jared Graves' Yeti SB66c - WINNING BIKE: Jared Graves' Yeti SB66c - Mountain Biking Pictures - Vital MTB
    You're making an apples to oranges comparison.

    He just can't ride a bike that isn't available yet, and he used the prototype 27.5 in July. The 5c that was available earlier had much less travel, making the 66 the bike to ride at the time. Once the 6" 27.5 was available, that was what he rode.

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    Quote Originally Posted by rockdude14 View Post
    This was a surprise to me too and my guess is bad testing methodology.
    Exactly. This, so called, test is a waste of time. They've made it look scientific by throwing lots of tech at it but they've totally failed to make the test comprehensive enough. You'd need to rack up a LOT of laps on a lot of bikes with riders who are used to all the sizes, yada yada. This test is irrelevant but what is annoying is the fact that, because it's done by a university and has lots of computers and sensors, it looks to the casual viewer that it really means something.

  39. #39
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    Quote Originally Posted by richde View Post
    Graves didn't run a 26 all season long, neither did Anne-Caroline, and none of the teams that ran 26 did it while there was a 27.5 option available. As soon as one became available, even though they weren't available to the public, the racers swapped over.

    Downhillers did the same thing.

    It really is more the rider than the bike in most cases, but at the same time, they're not going to skip on taking an advantage when it's available.

    Keep in mind that Yeti already had a 26 with Enduro geometry (same with DH bikes/teams), so making the huge investment in new molds for a new carbon frame is no small matter.



    1st year of the EWS you simply can't argue with those results. Not sure why anyone would look for excuses as to why 26 consistently took top spots over the whole season. Yes it's all about the rider but there is no rider in the EWS that can win with a wheel size that gives up seconds over multiple stages. Those results should speak volumes considering 27.5 is supposed to shave 1 second/X distance...

    You need to realized the 26" bikes that were winning, (JC's cannondale, Graves 66) were discontinued before the 27.5 replacements came out. It's not like those models lived side by side. Pros for those companies had no choice but to run the replacement models for better or worse, and of course they aren't going to say the discontinued model you can't buy was just as good or better. What really doesn't add up is why any company would think they need to change the bike when they just took top spots?

    What we saw is 27.5 didn't hurt Graves. This backs up bikeradar's negligible difference on paper, and only slight disadvantage for 27.5 on the DH. Since all riders were on 27.5 after the 66 was discontinued its a level playing field and we as consumers were cheated out of seeing real world race results.

    Companies put pro riders on the bikes they want to sell. THere's an interview with Curtis King where he admits specialized asked him to ride the Enduro 29. He kind of became the 29 poster boy because of that. When the Enduro 650 came out he was "given the green light" (quote from interview) to ride 27.5. What needs to be taken with a grain of salt is what pros ride, not objective tests like bikeradar's.

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    Quote Originally Posted by slimat99 View Post
    1st year of the EWS you simply can't argue with those results. Not sure why anyone would look for excuses as to why 26 consistently took top spots over the whole season. Yes it's all about the rider but there is no rider in the EWS that can win with a wheel size that gives up seconds over multiple stages. Those results should speak volumes considering 27.5 is supposed to shave 1 second/X distance...

    You need to realized the 26" bikes that were winning, (JC's cannondale, Graves 66) were discontinued before the 27.5 replacements came out. It's not like those models lived side by side. Pros for those companies had no choice but to run the replacement models for better or worse, and of course they aren't going to say the discontinued model you can't buy was just as good or better. What really doesn't add up is why any company would think they need to change the bike when they just took top spots?

    What we saw is 27.5 didn't hurt Graves. This backs up bikeradar's negligible difference on paper, and only slight disadvantage for 27.5 on the DH. Since all riders were on 27.5 after the 66 was discontinued its a level playing field and we as consumers were cheated out of seeing real world race results.

    Companies put pro riders on the bikes they want to sell. THere's an interview with Curtis King where he admits specialized asked him to ride the Enduro 29. He kind of became the 29 poster boy because of that. When the Enduro 650 came out he was "given the green light" (quote from interview) to ride 27.5. What needs to be taken with a grain of salt is what pros ride, not objective tests like bikeradar's.

    All of which depends on the myth of most manufacturers not being pulled, kicking and screaming, into making 27.5 bikes. They were so into the idea that it took until now for Specialized to make a real 27.5 frame.

    While bikeradar's test seems to appear objective, it could easily be as faulty as the test that found that flats were as good as clipless on road bikes. Let's not pretend that there's some great conspiracy perpetrated by the industry powerhouse LOOK to force every pro road rider to use their pedals.

    Companies like Yeti, Santa Cruz and Cannondale put a shitton of money into racing for their bikes to win...they wouldn't put an inferior product under their pro riders. If you think they're that stupid, buying any of their bikes would be a questionable decision.

    Remember that the 26" size wasn't chosen for any reason other than convenience, if not for a problem sourcing tires, we could have all been riding 27.5 from the beginning and wouldn't even be having this conversation.

    What happened was that when 29" came out, people saw the advantages of bigger wheels, but packaging them into long travel frames is impossible Enter the 27.5.

    Here's an interesting article from 2012 before just about every major manufacturer came out with a 27.5. What?s Driving the 650B Explosion? Interviews, Tech Breakdown & More!

    Like I said before, if people think that companies wanted to spend millions on new molds for CF frames just to sell to a few early adopters, they're ****ing crazy.

  41. #41
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    Quote Originally Posted by mhopton View Post
    Yeah, but did they account for FUN? Which wheel is "funnest" to ride....?
    Didn't you read the Mastering MTB book?

    Bikeradar's relatively thorough study on wheel size comparison.-funchallengeskill.gif

    If the shit is too scary on your 26, maybe a shiny new big wheeled bike would be more fun. If it's too easy on your big wheeled bikes loaded with the latest and greatest, and you can't go any faster, maybe a 26" (or rigid SS with tires that come almost bald) would be more fun.

    The more honest companies said that 27.5 bikes basically got trickle down tech from wracking their brains on the challenges of making 29ers work well. Fitting every feature they wanted, with less compromise, getting a modern design, while 26" designs were neglected (left for dead), when major part makers started supporting the new wheel size. In a comparison between a modern 27.5 and a truly modernized 26" (ex. Evil Uprising), the 26" wasn't really any worse. The 29ers that did come out right, get praise like, "why ride any other wheel size when a 29er rides this well." The others that embraced 27.5 seemingly gave up on solving the the challenges 29ers posed, but saw great potential and excitement in the newer option. I think 29ers still have a way to go, but I credit it for bringing out better engineered bikes and parts, like stiffer forks (34 and Pike in 120mm travel with tapered steerer and thru axle), better wheels, more emphasis on lesser known geometry figures like offset, trail, stack, reach, etc., Boost 148, Cannondale's F Si offset dropouts, 1x11, Shimano's side-swing FD, components that lower grip height (fitting smaller riders), and general material science developments to make frames and components lighter and stiffer. I guess you can say 29ers are the reason 27.5 exists too, well that and how 26ers apparently stopped selling.

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    Quote Originally Posted by richde View Post
    Graves didn't run a 26 all season long, neither did Anne-Caroline, and none of the teams that ran 26 did it while there was a 27.5 option available. As soon as one became available, even though they weren't available to the public, the racers swapped over.

    Downhillers did the same thing.

    It really is more the rider than the bike in most cases, but at the same time, they're not going to skip on taking an advantage when it's available.

    Keep in mind that Yeti already had a 26 with Enduro geometry (same with DH bikes/teams), so making the huge investment in new molds for a new carbon frame is no small matter.
    Not true, Sam Hill was on a 26er last year when the majority of the field was on 27.5.
    When he wasn't injured, he won a couple of races As far as DH is concerned 27.5 doesn't hold an advantage over 26ers. Hill proved that.

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    It is more about riding style,person choice and type of terrain you used to ride,by here I ride in wild track in Brazil rain forest, not hand made curse,not baby face track,I find my E29 is perfect to those kind of track,it doesn´t has big jumps ,I don´t kown what meant some guys when says "29er also reduces the maneuverability..." my person experience here I can do better the tight turns!

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    Quote Originally Posted by Mr Pig View Post
    Exactly. This, so called, test is a waste of time. They've made it look scientific by throwing lots of tech at it but they've totally failed to make the test comprehensive enough. You'd need to rack up a LOT of laps on a lot of bikes with riders who are used to all the sizes, yada yada. This test is irrelevant but what is annoying is the fact that, because it's done by a university and has lots of computers and sensors, it looks to the casual viewer that it really means something.

    A wheel size comparison is never going to be perfectly scientific with no external factors.

    Bikeradar has nothing to gain by making 27.5 look bad. There's zero incentive to make 26 look good. Making 26 look good throws a monkey wrench into every companies cogs. Even the few companies still offering 26 aren't marketing them, they are marketing 27.5.

    Be skeptical when imperfect tests make something that many stand to profit off of look great. This most certainly isn't that.

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    Bikeradar's relatively thorough study on wheel size comparison.

    Quote Originally Posted by SV11 View Post
    Not true, Sam Hill was on a 26er last year when the majority of the field was on 27.5.
    When he wasn't injured, he won a couple of races As far as DH is concerned 27.5 doesn't hold an advantage over 26ers. Hill proved that.
    You mean other than the other teams moving to 27.5?

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    Quote Originally Posted by SV11 View Post
    Not true, Sam Hill was on a 26er last year when the majority of the field was on 27.5.
    When he wasn't injured, he won a couple of races As far as DH is concerned 27.5 doesn't hold an advantage over 26ers. Hill proved that.
    Brycland took his first WC win ever this year on 26. This was against the same guys that had been beating him for years only now they were all on 27.5. (yes I know he won because he's hitting his prime, but it doesn't change the fact that his first win came against 27.5 bikes)

    Like others who won on 26, they continued to do so on 27.5. There's no real advantage one way or the other.

  47. #47
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    While I understand the old "26 is what was available" thing regarding the old school choice to use it for manufacturing... IF 27.5 were the holy grail, and true intended size, then doesn't it make sense from a research/performance/staying-true-to-the-original-intent thing that 27.5 should have come before the 29r?

    I thought it was telling, how Graves bested the field on a 26 whilst the 27.5 marketing machine was hard at work proving how it was faster with all their "on paper" flim flam.

    Is George Lucas behind the wheel size story? Because I still don't buy it.

    Either way it doesn't matter, in a years time I'll probably be on a 27.5 as well. But I won't be unloading my 26 wheels any time soon. I'll ride whats fun, and what works best for me. I'll even give 27.5 a fair shake at some point...
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    Quote Originally Posted by slimat99 View Post
    A wheel size comparison is never going to be perfectly scientific with no external factors.

    Bikeradar has nothing to gain by making 27.5 look bad. There's zero incentive to make 26 look good. Making 26 look good throws a monkey wrench into every companies cogs. Even the few companies still offering 26 aren't marketing them, they are marketing 27.5.

    Be skeptical when imperfect tests make something that many stand to profit off of look great. This most certainly isn't that.
    But they do stand to profit by spending as little as possible on the test and than writing an article claiming they've done scientific testing finally answering the most asked question of which is the best wheel size ever.

    I really want to see the article if this is used for academia like it seemed. I'm currently reading a pretty boring article on coeffecients of frictions for work and the number of samples used was more like 30-40 and there's basically no external factors for those tests. A test with uncontrollable external factors needs even more samples to try to prove anything. I can't imagine anyone publishing a journal article with a sample size of 1 (or 3 depending how you look at it).

    Just because they don't stand to profit doesnt mean bad testing methodology is ok and wont skew the results.

    Of course nothing with a human can remove all external factors. Again thats not a reason to through you hands up and say 1 sample is going to be as good as it gets and accepts the results.

  49. #49
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    Quote Originally Posted by tbmaddux View Post
    Not surprised to see an XC course coming out with 29ers faster.

    A little hard to parse what Hurst was saying, but my interpretation was that all the data they logged found no differences between the 3 options. The only significant findings were from the stopwatch.
    None of the findings were significant. He comments about no significant differences, but says there were practical differences. This, is nonsense. If data is not statistically significant, then no conclusions can be made about it. They observed slightly better times with 29ers, but they could not show that this difference was not due to random chance, or to factors other than wheel size. Pretty sloppy comments by this guy who has credentials, apparently.

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    Quote Originally Posted by slimat99 View Post
    I've tested 3 650b bikes. All felt slightly more awkward than 26 with nowhere near the freight train speed of 29.

    Before the slanted 650b marketing blitz pinkbike did an objective comparison and 650 came in last too.

    I wish Specialized had the sack to stick to their guns when they said 27.5 was unnecessary.


    Well, you know how it is with Spec, someone walked in with a big fat wallet asking for 650b. Then, Pooof, Spec produces one and that wallet is thinned out.

    It does not matter if it's the best of both worlds or does nothing well. If enough want a 650b, the bike companies will make them
    Crusin' on a fake duck with a Sharks jersey on and a pig's tail in my fork.

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    Im fairly sure i heard him saying the 29er required less energy to get round the course than the other two bikes did..multiply that by 10 or 15 laps and come to your own conclusion

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    I still have a sh!t load of fun on my 26er. I have ridden all three wheel sizes. 29er have their place, but not where I like to be.
    Crusin' on a fake duck with a Sharks jersey on and a pig's tail in my fork.

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    Quote Originally Posted by bigyin View Post
    Im fairly sure i heard him saying the 29er required less energy to get round the course than the other two bikes did..multiply that by 10 or 15 laps and come to your own conclusion
    You cant take something that might be statistically insignificant and multiple it by 10-15 to come up with a conclusion.

    I just flipped a coin 10 times and got 7 heads. That doesn't mean if I flip it 10000 times I'm going to get anywhere near 7000 heads.

    He had one sample per rider. You can't even find what the standard deviation is with only one sample to begin to figure out if the results are significant.

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    Ill make my own mind up thanks

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    Quote Originally Posted by SV11 View Post
    Not true, Sam Hill was on a 26er last year when the majority of the field was on 27.5.
    When he wasn't injured, he won a couple of races As far as DH is concerned 27.5 doesn't hold an advantage over 26ers. Hill proved that.
    Unfortunately, you need to try a little bit harder.

    Sam Hill, and the entire CRC team run a prototype 27.5 frame, that isn't available to the public.

    WINNING BIKE: Sam Hill's Nukeproof Pulse 27.5 - WINNING BIKE: Sam Hill's Nukeproof Pulse 27.5 - Mountain Biking Pictures - Vital MTB

  56. #56
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    Quote Originally Posted by rockdude14 View Post
    You cant take something that might be statistically insignificant and multiple it by 10-15 to come up with a conclusion.

    I just flipped a coin 10 times and got 7 heads. That doesn't mean if I flip it 10000 times I'm going to get anywhere near 7000 heads.

    He had one sample per rider. You can't even find what the standard deviation is with only one sample to begin to figure out if the results are significant.
    Exactly

  57. #57
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    Quote Originally Posted by CuddlyToast View Post
    Unfortunately, you need to try a little bit harder.

    Sam Hill, and the entire CRC team run a prototype 27.5 frame, that isn't available to the public.

    WINNING BIKE: Sam Hill's Nukeproof Pulse 27.5 - WINNING BIKE: Sam Hill's Nukeproof Pulse 27.5 - Mountain Biking Pictures - Vital MTB
    Thats probably for 2015, but during 2014 he was on a 26er, it's not news to anyone, even his mechanic said the same thing, 26er all the way.
    I don't have to try a little harder, but you obviously do if you don't know that sam was on a 26er last year.
    Vitalmtb got it wrong, really wrong. I have that race on vid, he's on a 26er, not 27.5.

    Pro bike: Sam Hill?s Nukeproof Pulse - BikeRadar
    Check out the specs.

    In Pietermaritzburg, he rode an AM 27.5, while he was recovering. Made the switch back before the Australian RD, I think you're confused with that.

  58. #58
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    Quote Originally Posted by SV11 View Post
    Thats probably for 2015, but during 2014 he was on a 26er, it's not news to anyone, even his mechanic said the same thing, 26er all the way.
    I don't have to try a little harder, but you obviously do if you don't know that sam was on a 26er last year.
    Vitalmtb got it wrong, really wrong. I have that race on vid, he's on a 26er, not 27.5.

    Pro bike: Sam Hill?s Nukeproof Pulse - BikeRadar
    Check out the specs.

    In Pietermaritzburg, he rode an AM 27.5, while he was recovering. Made the switch back before the Australian RD, I think you're confused with that.
    I honestly dont know what to say. Clearly he is riding a 27.5 bike, and has been for most of the 2014 WC season.

    *edit* Even the article you posted said that hes riding a 27.5 version now.

    Spotted: Sam Hill's 27.5" Nukeproof Pulse DH Bike - Pinkbike



  59. #59
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    Quote Originally Posted by SV11 View Post
    Thats probably for 2015, but during 2014 he was on a 26er, it's not news to anyone, even his mechanic said the same thing, 26er all the way.
    I don't have to try a little harder, but you obviously do if you don't know that sam was on a 26er last year.
    Vitalmtb got it wrong, really wrong. I have that race on vid, he's on a 26er, not 27.5.

    Pro bike: Sam Hill?s Nukeproof Pulse - BikeRadar
    Check out the specs.

    In Pietermaritzburg, he rode an AM 27.5, while he was recovering. Made the switch back before the Australian RD, I think you're confused with that.
    The bike spec is in the linked article, including the wheels:

    Wheelset: Mavic Deemax Ultimate 26in

    Edit, The article says he is riding 26 and also 27.5, switching back and forth, apparently. It was written in June 2014.

  60. #60
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    Quote Originally Posted by smilinsteve View Post

    Edit, The article says he is riding 26 and also 27.5, switching back and forth, apparently. It was written in June 2014.
    Yes, he rode the 26 inch in cairns, but after that it was 27.5 for the rest of the season.

    Josh Bryceland will probably be the last WC rider to win on a 26 inch, which he did at leogang... the only major WC team still running 26 is Kona.

  61. #61
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    Quote Originally Posted by rockdude14 View Post
    But they do stand to profit by spending as little as possible on the test and than writing an article claiming they've done scientific testing finally answering the most asked question of which is the best wheel size ever.

    I really want to see the article if this is used for academia like it seemed. I'm currently reading a pretty boring article on coeffecients of frictions for work and the number of samples used was more like 30-40 and there's basically no external factors for those tests. A test with uncontrollable external factors needs even more samples to try to prove anything. I can't imagine anyone publishing a journal article with a sample size of 1 (or 3 depending how you look at it).

    Just because they don't stand to profit doesnt mean bad testing methodology is ok and wont skew the results.

    Of course nothing with a human can remove all external factors. Again thats not a reason to through you hands up and say 1 sample is going to be as good as it gets and accepts the results.
    This is an excellent post and is worth reading again, if you maybe didn't understand it the first time? ;0)

    Calling something science doesn't make it science, and unless you place the word 'bad' in front of the word science this certainly does not qualify. It fails on so many points it's not funny and I have no idea why we are wasting our time talking about it as if it means something. Just because someone has some sensors and computers, maybe even a lab coat, does not mean that what they have to say is automatically of value. These people are human like everyone else and just as capable of spouting garbage.

    He comments about no significant differences, but says there were practical differences.
    Yeah, what does that even mean?? He said it several times as if repeating nonsense would somehow make it logical.


    Quote Originally Posted by ziscwg View Post
    I have ridden all three wheel sizes. 29er have their place...
    Yip, on the road! Want all your trails to feel as smooth and boring as riding on the road? Want to get into this off-road thing but don't have the skill? Turn left and buy a 29er. Want to feel the ground and make every ride fun? Turn right for 26. And 27.5 is for the dolts standing in the middle zipping their heads back and forth saying "ooooOooooo no, which one?????'' ;0)

    Except of course my next bike will probably be 27.5 because that's all the b******'s are making now! :0(

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    It's funny to me how everyone cites these professional riders and what size they are riding, improving their run times by split seconds from one wheel size to another.

    If Sam Hill or any of the others mentioned are only gaining a few seconds by switching from 26 to 27.5, or vice versa, how much of a difference do you think wheel size makes to you?

    I doubt anyone in this forum is riding on that level, so just have fun and don't take this crap so personal just because you have X" tires and someone said that size may not be the best at doing XY and Z.

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    Quote Originally Posted by CuddlyToast View Post
    I honestly dont know what to say. Clearly he is riding a 27.5 bike, and has been for most of the 2014 WC season.

    *edit* Even the article you posted said that hes riding a 27.5 version now.
    What a load of bs, maybe it's safer to get it from the horses mouth, in this case his mechanic.

    https://www.youtube.com/watch?v=oIcaZuUhi8U

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    Quote Originally Posted by SV11 View Post
    What a load of bs, maybe it's safer to get it from the horses mouth, in this case his mechanic.

    https://www.youtube.com/watch?v=oIcaZuUhi8U
    That interview was in cairns. After that race, he rode a 27.5 version in each WC. I don't know why we're arguing, this has always been a fact.

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    Quote Originally Posted by richde View Post
    Somebody better tell that to all the DH and Enduro racers.
    Its not that you cant go as fast with 26 dh. It is rather the factoring of riding all day doing many stages and many climbs that add up fatigue. Winning is based on your cumilitive performance. Technically 26 takes the most work in undulating areas. While the data showed 26 fastest downhill, it also showed the triceps and biceps worked hardest with 26. 2013 enduro world series was won on 26 with only a 68 degree head angle bike. A bit of trail geometry by this years standards. 3Rd place jared graves was on an sb66 26er. 2014 was won on sb6 27.5. I still think 2014 could have been won on 26 but thats not what the market is doing so we will never know. In the end you talking about a hand full of talented guys in the hunt. Winning and losing is the difference of a good day or a bad day at times. Let alone keeping your edge and just putting it together rite.
    Last edited by akiracornell; 02-05-2015 at 12:47 AM.

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    Quote Originally Posted by molon_labe View Post
    It's funny to me how everyone cites these professional riders and what size they are riding, improving their run times by split seconds from one wheel size to another.

    If Sam Hill or any of the others mentioned are only gaining a few seconds by switching from 26 to 27.5, or vice versa, how much of a difference do you think wheel size makes to you?


    Edit::: i didnt mean for this response to your comment. I got a little lost in reading and commenting

    I doubt anyone in this forum is riding on that level, so just have fun and don't take this crap so personal just because you have X" tires and someone said that size may not be the best at doing XY and Z.
    my apologies as this response wasn't meant for your. I was reading and randomly responding on my cell phone. not sure how I ended up here. but in any case I did conclude this:

    I think the test quite eloquently showed that wheel size is not a huge factor. A good rider is a good rider. He is gonna perform on whatever. I didnt insinuate the results as 27.5 is the slowest by any means.
    He claimed to use seasoned xc racers, all of whom i would bet race their season on 29ers and to which they are most comfortable with. if anything i would think the 26 would cause the most mental handicap from the go. But it didnt downhill on the given coarse. Then even the host was a rider whom claimed he didnt know what bike he was the fastest on and just gave it his best go.
    By experience i can assume fatiguing is a factor that affects timed performance. another factor we cant accurately factor.
    The one conclusion is it appears with the biggest wheel got the edge on a full loop. I did find it interesting 26 had then edge going down. I would assume it may had to do with cornering on this given coarse. Again im just assuming. I personally can feel 27.5 carries and rolls faster than 26. In the end i didnt think 26 would be the winner on the dh on an xc coarse over both other wheels.

    The comparison of 26 and 27.5 i find inconclusive. But i do find there is a clear winner climbing.
    Last edited by akiracornell; 02-05-2015 at 12:06 AM.

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    Quote Originally Posted by Preston67 View Post
    A 20 second/2% diff is very significant if it represents a real increase. I know in my races I would have gladly had a 2% increase it is the difference between podium and top 10. That's true for most of my classes whether its a 3 minute dh run or a 25 minute TT or a 2 hour XC race, 2% is huge. That being said I agree with the rest of your statement, if you ask me to go do a 15 minute fast lap, my 2nd and 3rd laps will be significantly slower. Doesn't seem like a valid test.

    >29ers = big boats

    >everyone finished laps faster on average when riding the 29ers
    he did say an hour of rest between laps but still. A multi day test randomizing the order of the bikes and riders may have shown a more clear cut correlation. I also considered you could get faster as you start refining your lines. it just seems there are too many variables to be concrete results for sure.

  68. #68
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    Quote Originally Posted by slimat99 View Post
    It would make sense that teams would go with equipment that offers the best chances to win, but what doesn't add up is 26 took 1st and 2nd in the EWS last year and was leading the overall this year before being removed from competition? Not sure why any company would say we need to ditch 26 for 27.5 with such results. If anything you would think companies would reevaluate moving away from a wheel size that dominated the podium in the discipline where 27.5 was supposed to shine brightest.
    here here.......cheers!!!!!!

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    Quote Originally Posted by rockdude14 View Post
    You cant take something that might be statistically insignificant and multiple it by 10-15 to come up with a conclusion.

    I just flipped a coin 10 times and got 7 heads. That doesn't mean if I flip it 10000 times I'm going to get anywhere near 7000 heads.

    He had one sample per rider. You can't even find what the standard deviation is with only one sample to begin to figure out if the results are significant.
    I thought it was multiple riders that were seasoned racers to help control the test so to speak.
    He never claimed how many though.
    In a test of human behavior we obviously not going to get a clear cut cause and effect relationship result.
    At best we may end up with a correlation which a lot of modern science is based on. i give him kudos for trying.

    the one thing all of us with common sense can see is there was preference to the 29 in climbing.
    for all we know, in this case the 27.5 could have had the most ineffective geometry.

    What I also did hear was the Dr clearly say "everyone has their own theories. So we want to do is.....TRY(keyword here try).....and add a LITTLE science to that. And we tryng to put some definitive answer to that.

    what he concluded was wheel size didn't seem to have a significant factor on the measured muscle test to be discernable. but all they had to go on was timed results. i find no fault in that and i would conclude if i were racing on the test track 29er is probably the way to go.

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    Quote Originally Posted by Mr Pig View Post
    27.5 is for the dolts standing in the middle zipping their heads back and forth saying "ooooOooooo no, which one?????'' ;0)
    Or maybe it's for people that appreciate the fun of a 26er, but are tall enough to appreciate the benefits of slightly better roll-over and maintained momentum.

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    Quote Originally Posted by mountainbiker24 View Post
    Or maybe it's for people that appreciate the fun of a 26er, but are tall enough to appreciate the benefits of slightly better roll-over and maintained momentum.
    Nice.

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    Quote Originally Posted by akiracornell View Post
    what he concluded was wheel size didn't seem to have a significant factor on the measured muscle test to be discernable. but all they had to go on was timed results. i find no fault in that and i would conclude if i were racing on the test track 29er is probably the way to go.
    There were no significant findings in the data. Not just on the muscle test, but with the times as well.
    So I find a lot of fault with the conclusions they tried to draw from a set of data that concludes nothing. I also find a lot of fault in calling it science.

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    "no statistical difference" = 19 seconds over 15 minute course

    "practical difference" = 0.001 second will win a race

    average joe = any wheel size will be fun, don't stress about it.

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    I think people should at least wait for the paper/s to be published before coming to conclusions on the quality of the science behind this.

    Seriously? Saying this is 'bad science' based on a BikeRadar youtube video? You have to be kidding me. You are always going to get some non-significant results based on the somewhat arbitrary, but accepted, value of P<0.05.
    That does not mean that there is nothing there, it just means that you need to run some more replicates. People get life in prison on less information than that, it's just that science happens to have higher standards.

    Are they going to call the lap time difference a result in their eventual academic publication without running more replicates? No, because that would be unscientific, and no respectable journal would publish it. BikeRadar is not bound by the same standards.

    I'm sure the researchers have plenty of data from the muscle sensors and gas analyser, if they felt the lap times were important they would have run more replicates. BikeRadar was interested in the lap times because they want to see which wheel size is 'best', so they focused the video on that part of it. As people have said in the thread, lap times for each wheelsize are going to be completely dependent on the course, and I'm sure the researchers know that too.

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    Quote Originally Posted by bing! View Post
    "no statistical difference" = 19 seconds over 15 minute course

    "practical difference" = 0.001 second will win a race

    average joe = any wheel size will be fun, don't stress about it.
    No statistical difference doesn't mean that 19 seconds doesn't matter, it means they haven't shown that the 19 second difference is real.

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    Quote Originally Posted by cerebroside View Post
    I think people should at least wait for the paper/s to be published before coming to conclusions on the quality of the science behind this.
    Maybe its the people in the study who should be waiting. Waiting until they have real science to back up the the conclusions they are putting out to the world.



    Seriously? Saying this is 'bad science' based on a BikeRadar youtube video? You have to be kidding me. You are always going to get some non-significant results based on the somewhat arbitrary, but accepted, value of P<0.05.
    If you don't like P<.05, then what do you propose to differentiate meaningless anecdotes from real data from which conclusions can be drawn?

    That does not mean that there is nothing there, it just means that you need to run some more replicates. People get life in prison on less information than that, it's just that science happens to have higher standards.
    Right. it means they had an inadequate sample size. Therefore they should stfu and quit posting fake "results" on line, because they have no results.
    The "higher standard" of science is simply a way to know if you can have confidence in a result or not.

    Are they going to call the lap time difference a result in their eventual academic publication without running more replicates? No, because that would be unscientific, and no respectable journal would publish it. BikeRadar is not bound by the same standards.
    Do you already know that they will publish in a journal? And what they will say?
    Bike Radar is not an academic journal, but any decent publication should be wise enough to weed out BS. And what about the authors? What should the standards be for guy who has the title of Doctor, and works at a university? Should he be taking meaningless numbers and proclaiming to the world he knows what the best wheel size is?

    I'm sure the researchers have plenty of data from the muscle sensors and gas analyser, if they felt the lap times were important they would have run more replicates. BikeRadar was interested in the lap times because they want to see which wheel size is 'best', so they focused the video on that part of it. As people have said in the thread, lap times for each wheelsize are going to be completely dependent on the course, and I'm sure the researchers know that too.
    Why do you try to differentiate between Bike Radar and the researchers, when the Bike radar video is a video of the researchers?

    They both want to proclaim that they have figured out what is best, but they haven't.

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    Unfortunately I don't have time for this right now, but:

    - The researchers are very careful to state what was found to be statistically significant, and what was not.

    - P<0.05 is fine and I don't have a problem with publishing to that standard. But if they got P=0.06 their results are now 'meaningless anecdotes.' They obviously feel confident enough in their results to call it one way or another in a casual setting, which is fine, and they clearly define what is significant and what is not. You have no idea what their actual results were without the publication.

    - It is common practice to report non-significant preliminary results at academic conferences with disclosure of the statistics, as part of larger presentation (as happened here.)

    I will try to come back and discuss this more later, it is an interesting topic!

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    Quote Originally Posted by cerebroside View Post
    Unfortunately I don't have time for this right now, but:

    - The researchers are very careful to state what was found to be statistically significant, and what was not.

    - P<0.05 is fine and I don't have a problem with publishing to that standard. But if they got P=0.06 their results are now 'meaningless anecdotes.' They obviously feel confident enough in their results to call it one way or another in a casual setting, which is fine, and they clearly define what is significant and what is not. You have no idea what their actual results were without the publication.

    - It is common practice to report non-significant preliminary results at academic conferences with disclosure of the statistics, as part of larger presentation (as happened here.)

    I will try to come back and discuss this more later, it is an interesting topic!
    I did not hear them say that any of the data was significant. but I did hear them say stuff like "29er wins", "26 is the fastest downhill", etc. They were not careful to point out that they did not show any of that to be true.

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    The big problem I have with this is that most people don't look very closely at how 'tests' and 'studies' were done. They just look at the result, see it comes from a university and accept it as truth. The average guy is just so gullible! :0(

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    I think it is very important to note that this study doesn't really mean anything and will not be considered "legit" unless the results can be replicated. Until others replicate these results, it's just a one off finding given the factors in the test.

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    Quote Originally Posted by smilinsteve View Post
    No statistical difference doesn't mean that 19 seconds doesn't matter, it means they haven't shown that the 19 second difference is real.
    uh, considering that 19 over 900 seconds is a 2% difference. by most measures, that is statistically insignificant given the methodology (wheel size placebo effect, variability in path taken by rider, variability in rider strength over test etc etc). this is pretty much what you said in the later part of your statement "it means they haven't shown that the 19 second difference is real". but you can think whatever you want to think. thats my opinion.

    if they did the test with an electric motor as a mule (for consistency and measurability) over a test track similar to say a treadmill, a repeated test that consistently had a 2% difference may proven something. but not with this test.

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    Quote Originally Posted by bing! View Post
    uh, considering that 19 over 900 seconds is a 2% difference. by most measures, that is statistically insignificant given the methodology (wheel size placebo effect, variability in path taken by rider, variability in rider strength over test etc etc). this is pretty much what you said in the later part of your statement "it means they haven't shown that the 19 second difference is real". but you can think whatever you want to think. thats my opinion.

    if they did the test with an electric motor as a mule (for consistency and measurability) over a test track similar to say a treadmill, a repeated test that consistently had a 2% difference may proven something. but not with this test.
    Uh, thanks for letting me think what I want to think, but I think you don't understand what I think.

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    Your welcome.

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    Quote Originally Posted by bing! View Post
    uh, considering that 19 over 900 seconds is a 2% difference. by most measures, that is statistically insignificant given the methodology (wheel size placebo effect, variability in path taken by rider, variability in rider strength over test etc etc). this is pretty much what you said in the later part of your statement "it means they haven't shown that the 19 second difference is real". but you can think whatever you want to think. thats my opinion.

    if they did the test with an electric motor as a mule (for consistency and measurability) over a test track similar to say a treadmill, a repeated test that consistently had a 2% difference may proven something. but not with this test.
    Did I miss it, or why didn't they use a power meter?
    Someone here kept insisting it takes more power to maintain speed with 29" wheels vs 26" wheels so that should be easy to prove or disprove, either measuring power at a given speed or speed at a given power output, for each wheel size.

  85. #85
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    Quote Originally Posted by fsrxc View Post
    Did I miss it, or why didn't they use a power meter?
    Someone here kept insisting it takes more power to maintain speed with 29" wheels vs 26" wheels so that should be easy to prove or disprove, either measuring power at a given speed or speed at a given power output, for each wheel size.
    They did use a power meter. See 1:35 of part one

    https://www.youtube.com/watch?v=vhS1HfvBeYA

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    Quote Originally Posted by fsrxc View Post
    Did I miss it, or why didn't they use a power meter?
    the link the OP is part 2/2. in the first part, they show the bikes and they are in fact using SRM power meters.

    using an electric motor is useless IMHO. we already know the rolling resistance of tires, and we know that 29ers win that contest.

    it was useful to try to figure out what people can ride faster, but I don't think their sample size was large enough and their testing methodology had some compromises.

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    So I agree we need to see the details to see if this study is worth a damn...but I have already come to the same conclusions by just riding bikes.

    I own a 6inch 26in bike AM bike, a 26in DH bike, and a 29er hardtail XC race bike. My riding group has a few 27.5in bikes rolling around. My old race bike was a 26in carbon hardtail.

    I am faster on the 29er and FEEL faster on the 29er. It floats over things. It is 1.5# heavier than the 26in race bike, but still faster.

    We just finished building up a 27.5in wheelset for my buddy a few weeks after I finished building up my 26in carbon wheelset. It just isn't that big of a difference in size. Do I think it is going to be "slower" than my 26in bike if built up the same...probably not. But it isn't really going to be any faster for us slobs riding 6inch bikes on the trails. It was shoved down our throats, and we ate it up. It isn't a necessary wheel size.

    It's here to stay. I'm bummed about not getting all the new tire designs I want, and I'm grumpy. But the 27.5 revolution isn't REALLY about performance, it's about dollars. You guys handed out the dollars so now it exists.
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    Or maybe it is a study with limitations and you take what you can from it.

    The use of a motor provides more control over the experiment. You take away variability, you can test better for smaller differences.

    I am however fully content to accept that the differences are marginal, whichever has an advantage, and that's what I took from the experiment.

    It's not as if there is anything of dramatic significance. If people should decide to sweat over a 2% difference, maybe a carbon bar will help

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    Another scientist here, I found the science involved to be quite dodgy, it may not be, but that is how it is portrayed in the video clips.

    A few specific issues I have:

    No statistical significance reported, the faster lap times on the 29 could be a completely random occurrence.

    Lack of familiarization in the 27.5 has made their results completely flawed, the riders hadn't even ridden a 27.5 before... wondering why it did worse?

    No mention of randomization of bikes, an order effect can and will occur if randomization doesn't occur, I presume randomization will and did occur, but a small detail so probably not mentioned.

    The number of participants and numbers of laps required, over a number of different sessions will be needed, this will be worked out via a power analysis, no mention of it occurring, probably did, but presenting data from such a tiny sample is in essence bad science, it just pointlessly confuses the layman.

    I'll be curious to read the published article... if it makes it through the peer review process.

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    in my theortical opinion..... if you gave me a 26", a 29 and then 27.5 all which i had never ridden before, I don't think im gonna have trouble learning 27.5 anymore than any of the other bikes. i still have to figure out the wheel base in the corners and get seat and stem set up to mash. other that im just gonna go. you know most of these test guys probably hadn't ridden 26 in years being xc racers. i imagine they would have to acclimate to the geo of all the bikes. learning a bike you have never ridden johny on the spot no matter the wheel size. Its gonna be instinctual on all the bikes anyway. i think 27.5 should have made me faster up hill. who knows? my guess is the geometry wasn t right. maybe it sat too high or something, with out the full advantage of the 29 roll and low shreddy feel of 26. 27.5 just got stuck in the middle not inspiring the full confidence in either direction. i don't know/

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    Quote Originally Posted by rockdude14 View Post
    If I remember correctly it was 3 riders doing 1 lap per bike. With times around 15minutes a 20 second difference is a whooping 2% difference. I'm not a statistician but this seems like it could easily be in the margin of error. Especially when none of the riders had experience on the bike that was the slowest at everything, I don't think that's negligible. Hell on a 15minute segment on the exact same bike that I have ridden for multiple years a lot of my times dont fall within 20 seconds of each other.

    They should have saved the money from the **** ton of sensors and used it to test it multiple times over the course of a week.
    But they also measured power and mentioned the least effort was on the 29er, so taking that over a long ride and you could surmise you'd end up faster on the 29er since toward the end of the ride you'd have exerted less effort.
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    Quote Originally Posted by TwoTone View Post
    But they also measured power and mentioned the least effort was on the 29er, so taking that over a long ride and you could surmise you'd end up faster on the 29er since toward the end of the ride you'd have exerted less effort.
    Yes. I don't think some folks were paying attention that closely to the 2 videos.

    We know 29ers have slightly better rolling resistance, and even a smaller amount of better angular rollover. We know it! Just like we know that a 29er wheel & tire combo of the same model & cost as a 26" equivalent will weigh more, and shockingly, it's bigger as well.

    To me the mystery in this test is 27.5. A larger sample size would have helped a lot, IMO.

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    Except, they plainly state, twice, at the beginning of the second video that there is NO scientific difference between the three bikes when all of the measurements are analyzed. What that means is that we would expect the results we got due to chance often enough that it is fairly likely for this particular sample. Think of all the variables you can't control for: Temperature, humidity, changes in track conditions, wind direction, operator choices in line on a particular lap which taken together or separately could effect times/power more than wheel size. Once the result is acknowledged as falling under a p value we set as indicating we are fairly confident isn't due to chance, then no real world extrapolations can be made, since we don't know what we are basing those extrapolations on. That being said, I will be interested to see the data if/when it is published as it might be indicative of doing further, better constructed experiments.
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    These tests and debates make me chuckle.

    One size doesn’t fit all……..I have been riding 29’ers for over 10 years and I can say with 100% certainty that I am faster on a 29’er…way faster. However let me explain a few things……Me 6’2” and ride XC and Trail…most of my rides are 15-25 miles and over 3K to 6K of climbing. What the 29’er does for someone my size and my type of riding is maintain momentum, corner and go over obstacles better than a 26” wheel. What it doesn’t do better is accelerate.

    Now my middle boy (13) that rides enduro / trail is faster on a 26” wheel than 27.5” or 29”. The reasons are his riding style, suspension (170mm front / 150 rear) and height (5’2”). He has a low center of gravity and likes more travel so the 26” wheel is better for HIM and HIS riding style.

    Over the years I have seen shorter people (5”-5-4”) ride 29’ers for no other reason than the hype. Also I have seen 6’-2”-6’8” riders ride 26” wheels and refuse to try anything else…….because that is what they knew.

    With all things equal it comes down to two things (1) Riding Style (2) Rider Height. If I was into more “Enduro / All Mountain” riding I think I would be faster on a 27.5” bike than a 29”er....who knows

  95. #95
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    Quote Originally Posted by IPunchCholla View Post
    Except, they plainly state, twice, at the beginning of the second video that there is NO scientific difference between the three bikes when all of the measurements are analyzed. What that means is that we would expect the results we got due to chance often enough that it is fairly likely for this particular sample. Think of all the variables you can't control for: Temperature, humidity, changes in track conditions, wind direction, operator choices in line on a particular lap which taken together or separately could effect times/power more than wheel size. Once the result is acknowledged as falling under a p value we set as indicating we are fairly confident isn't due to chance, then no real world extrapolations can be made, since we don't know what we are basing those extrapolations on. That being said, I will be interested to see the data if/when it is published as it might be indicative of doing further, better constructed experiments.
    Your part in bold is wrong. What it means is that the measured differences fall within the margin of error for this experiment.

    They attempted to control temperature, humidity and track conditions by doing all tests on one day. I don't think the survey could have been done better except by repeating it with more riders, and setting up similar tests on different tracks. But more test cases costs time and money, and I'm sure they already spent a ton on this.

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    How is margin of error different from chance? Serious question, been a while since I took statistics. My understanding is that something falling within the margin of error means that we can not tell if the results are due to actual measured differences or to the randomness inherent in measurements, in other words chance. Even if that is wrong doesn't falling within the margin of error still mean that we have no way of knowing what the results mean? I understand that they attempted to control for those differences by running the results on the same day. That is not saying the same thing as that they actually controlled for them. To make it a valid test that we can draw any conclusions from the results have to fall outside the margins of error. Otherwise we are basing our extrapolations on, well, nothing.

    Personally, I think it is interesting that even controlling as much as they did, there was no significant difference between the wheel sizes. This might point to the fact that wheel size plays less of a roll than all of the other myriad factors that go into a bike and its operator and its environment.
    It's just a flesh wound!

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    I don't care what any study says, my strava times confirm that i'm faster on 27.5 than 26 and that's been proven out to me over 6 months of riding both wheel sizes with identical geometry and travel. the difference isn't enough to not be completely negated by how I'm feeling on that particular day, but all things being equal the 27.5 is faster and more confidence inspiring than the 26, for me. I can be just as fast on the 26 but i have to concentrate more, the 27.5 is easier to ride faster. I like riding steep, fast, technical trails, not groomed xc trails, so that's probably a contributing factor, too. I have never ridden a 29 so can't comment on that.
    nothing witty here...

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    Not a single helmet visor. Not a single (hidden brake finger-induced) brown pow-ing of a corner. Not a single whew-bro dogpile of affirmation after each lap.

    This study's data is untrustworthy at best.

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    Quote Originally Posted by DeeZee View Post
    The 26" GT Avalanche Expert is now a 27.5".......by definition it is dead :-)

    My son's 26" SC Nomad serves him very well! :-)
    shhhh lol

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    No I didn't read this entire thread. No I don't really want to. Yes I will be ridiculed for posting without reading it.

    I think the industry is missing the boat entirely. The relative difference among the verious wheel sizes is peanuts compared to the difference among myself and my riding buddies legs. I can scientifically say that those with longer legs are faster than me.

    How can I increase my legs' length? If the industry can nail that one down they might have something.

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    Quote Originally Posted by bad andy View Post
    I can scientifically say that those with longer legs are faster than me.
    I can scientifically say that those who are less fat and have lighter bikes are faster than me. Except going up steep hills for some reason.

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    Quote Originally Posted by Mr Pig View Post

    Except of course my next bike will probably be 27.5 because that's all the b******'s are making now! :0(

    I agreee. I will probably be stuck with some 650b crap because you can't get 26 anymore. Although, I did see some great frame deals recently for 26ers
    Crusin' on a fake duck with a Sharks jersey on and a pig's tail in my fork.

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    Quote Originally Posted by ziscwg View Post
    I agreee. I will probably be stuck with some 650b crap because you can't get 26 anymore.
    Bingo! I've just ordered a Commencal Meta SL 2 from their factory shop and it's a 26'' bike. Happy days :0)

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    Quote Originally Posted by bad andy View Post
    No I didn't read this entire thread. No I don't really want to. Yes I will be ridiculed for posting without reading it.

    I think the industry is missing the boat entirely. The relative difference among the verious wheel sizes is peanuts compared to the difference among myself and my riding buddies legs. I can scientifically say that those with longer legs are faster than me.

    How can I increase my legs' length? If the industry can nail that one down they might have something.
    How can I increase my legs' length? If the industry can nail that one down they might have something

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    Quote Originally Posted by DeeZee View Post
    How can I increase my legs' length? If the industry can nail that one down they might have something

    Done.........
    Is that Five Ten? I want one.

  106. #106
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    There are instances in other sports where the hybrid design loses. One that comes to mind is surfing. Take the fun board for instance. Yes, there are many great fun boards (I even have one) but in the end nothing truly paddles like a long board or rips like a short board. Fun boards try to take the best of both, but many end up with the worst of both. Not saying this is true for 27.5 but something to consider. That said, who really cares, this is why I rock a 7'8" fun board when everyone else is on an 11' plank.

  107. #107
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    Quote Originally Posted by chowdapilot View Post
    There are instances in other sports where the hybrid design loses. One that comes to mind is surfing. Take the fun board for instance. Yes, there are many great fun boards (I even have one) but in the end nothing truly paddles like a long board or rips like a short board. Fun boards try to take the best of both, but many end up with the worst of both. Not saying this is true for 27.5 but something to consider. That said, who really cares, this is why I rock a 7'8" fun board when everyone else is on an 11' plank.
    Good analogy!

  108. #108
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    Mechanical Engineer here. My take; the study is not well designed so it doesn't seem to give a definitive result.

    Prior to this study the general descriptions we've all read about the ride 'feel' of the different wheel sizes seem to be reasonable.

    If BikeRadar didn't have identical 'calibrated' rear shocks, (not really possible, so why not go to a rigid bike or at least a hardtail) then the effect of that will swamp most other effects in this test. There are other relevant studies that would indicate that. (see below). So here in this test for off-road I'd put forward the theory that the effect of rear shocks will simply dwarf any differences due to wheel size and if the shocks are un-calibrated then there will be no meaningful data or conclusions to be drawn. Remember shock-dampening converts energy to heat.

    IMO This study has too many variables. Measuring lots of things doesn't account for the massive effect of the different bikes. They didn't even mention the tyres from my viewing of the video. Or a discussion of how the rear shock may have had the biggest impact.

    That would be the conclusion drawn from reading Jan Heine's testing; in his Bicycling Quarterly magazine, he's done a series of tests, that in total, are GREAT. They shows this one up. There's a reason to simplify testing into simpler chunks.

    https://janheine.wordpress.com/2012/...ance-of-tires/

    https://janheine.wordpress.com/2010/...-and-pressure/


    Jan's series of tests show that the suppleness (lack of dampening) of the tyre sidewall plays the biggest part in rolling resistance of a 'rigid' bike, not tyre diameter or even pressure much. Elsewhere Jan tests the effect of supple frames, even one with a rear 'elastomer' suspension.

    I hope BikeRadar do more tests with all that cool gear they have. I want one of those facemasks!

  109. #109
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    There are not any bikes truly identical between 26, 27.5 and 29 other than wheel size because the frame and fork (plus obviously wheels and tires) must change to accommodate the wheels. You could not even build such a thing as the geometry would be wildly different using 26" wheels on a 29er frame.

    They did use identical components, including shocks, fork, wheel brand, tire brand, model and width, and they set the suspension sag for each rider.

    No coincidentally, this mirrors the real world when a rider uses a 26, 27.5 or 29 that are highly similar.

  110. #110
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    Quote Originally Posted by ColinL View Post
    .....
    They did use identical components, including shocks, fork, wheel brand, tire brand, model and width, and they set the suspension sag for each rider.
    Hey Colin,
    and there is the problem with the test. 'Identical' rear shock and fork will not be Identical in performance. Calibration much? Mirroring the real world spoils the validity of the test.

    A good test would use the same rigid frame and fork and swap wheels only. And get three riders to ride each wheel size. Any decent framebuilder could make a test-mule rigid frame and rigid forks, that had three sets of dropouts, to enable swapping of the wheels, brake-calipers and rear derailleur mounting. The bike would look ugly, but it really WOULD give some fantastic data. Come to think of it, any of the boutique full-suspension frame-makers could make a test-mule bike like this too. THAT would be a great test and great video/reading !

    The BikeRadar readers would learn something, and there could be a second, big 'sales' opportunity for BikeRadar. And we'd respect them all the more for having sought to improve on their first effort.

    That is why I find Bicycling Quarterly magazine such a great read. No connection to them here.

    Cheers,
    Ewen

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    "No statistical difference" gets trumped by "real world difference." ??!

    This person is not a scientist, but is surely an idiot.

  112. #112
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    Quote Originally Posted by e.gellie View Post
    A good test would use the same rigid frame and fork and swap wheels only. And get three riders to ride each wheel size. Any decent framebuilder could make a test-mule rigid frame and rigid forks, that had three sets of dropouts, to enable swapping of the wheels, brake-calipers and rear derailleur mounting.
    The testing wasn't about purely scientific numbers. As I've said before in this thread, it is easy to test rolling resistance, approach angle, and so on. And people have already done that. This test was attempting to know what people can ride the fastest and if their body is actually more efficient riding one wheel size or another.

    Going rigid punishes the rider and rewards the smoothest line, whereas full suspension riders can and often do choose alternate lines, because their equipment allows them to do so. Pretty soon we're testing 29ers on slicks and calling road bikes mountain bikes... And there's the very obvious issue that fatbikes aside, hardly any fully rigid bikes are being sold right now in comparison to hardtail and full suspension.

    ...WAIT! Damn, that's it. The test is total crap, they didn't test fatbikes.

  113. #113
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    This study lends more evidence towards the theory that the industry arbitrarily eliminated 26" wheels. Real world results from Enduro races where 26" beat out 27.5" is the proof in the pudding. All that being said, my next bike will be a 650B, but not by choice.

  114. #114
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    Honestly this guy on youtube does great comparison videos.https://www.youtube.com/watch?v=-YPbSU3hgTQ

    I think all the bikes and different wheelsizes are great. I love 26", I have one. I also have a carbon 29er hardtail and love love love that bike. And Now Im building a 650b Blur TR and Im probably going to love that bike too. People get their panties in a bunch.
    2014 27.5" SC Blur TRa:cool: - 2014 IP-106 Chiner 29er :nono: - 2005 Fuji Team SL 16.2lbs -:thumbsup:

  115. #115
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    Quote Originally Posted by saidrick View Post
    This study lends more evidence towards the theory that the industry arbitrarily eliminated 26" wheels. Real world results from Enduro races where 26" beat out 27.5" is the proof in the pudding. All that being said, my next bike will be a 650B, but not by choice.
    If you don't want 650 why buy one? 26 will for sure die out when even those that want 26 buy 27. There are 2015 26" options, and how well these sell very well may spell the end or continuation of 26. Kona Process 167, Knolly Chili, Banshee Rune/spitfire, Transition Suppressor, Evil Uprising......

    The only real voice any of us have is with our wallets.

  116. #116
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    Quote Originally Posted by slimat99 View Post
    There are 2015 26" options
    Realistically, the choice is limited and buyers are already shunning them. I reckon 26'' trail bikes will be very thin in the shops within a year or two.

  117. #117
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    Quote Originally Posted by Mr Pig View Post
    Realistically, the choice is limited and buyers are already shunning them. I reckon 26'' trail bikes will be very thin in the shops within a year or two.
    WTB has apparently decided to not produce new tire models in 26", instead offering only 27.5 and 29. I don't know if anyone else has started this yet, or discontinued production of existing 26" models, but it's coming.

    26" tires and wheels won't get to be as scarce as 650B once was, say 8 years ago, but it is absolutely declining.

  118. #118
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    I think for those shopping the 26/27.5 market it would only be a very very small percentage that would really feel the need for the extra manoeuvrability of the smaller wheels.
    For the vast majority the slightly bigger wheel size really does offer so many benefits with almost no drawbacks, of which only the hardcore rider would really demand.
    It would be great if the market could support all three wheel sizes and give everyone, even the small minority, what it wants. But I can't imagine that's the case.
    And for that reason it will come down to choosing between 27.5 and 29. And there you have very real, noticeably different ride characteristics. And the consumer can choose which one he or she prefers, as opposed to being told which one to ride.

  119. #119
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    It would be cost prohibitive for them to have actually created a proper peer reviewed and repeatable scientific study. I commend them for working with what they had.

    That said, they said XC racing many times, and the terrain they showed is what I'd call VERY mild, very smooth easy XC.

    If those were my trails, well if I didn't just quit the sport out of boredom, I'd run a hardtail 29er clearly. That's going to be the fastest bike on those trails and I don't need sensors to tell me that.

  120. #120
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    Quote Originally Posted by Mr Pig View Post
    Realistically, the choice is limited and buyers are already shunning them. I reckon 26'' trail bikes will be very thin in the shops within a year or two.
    This is already the case. All the major companies have dumped 26" from all but their entry level MTB's. Spesh, Trek, Giant, C'dale are nearly devoid of the wheel size other than the intro bikes and the exceptions below.

    26" is still available for DH and DJ, but the move to 650b for the "playfull" wheel size is already happening there too.

  121. #121
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    Quote Originally Posted by Mr Pig View Post
    Realistically, the choice is limited and buyers are already shunning them. I reckon 26'' trail bikes will be very thin in the shops within a year or two.
    This is why I'm saying if you want 26 spend your money this year or you may be stuck with 650. There are multiple 26 options for 2015, none of which are being marketed so many don't even know they exist. Just because your LBS doesn't stock 26 shouldn't stop anyone from buying what they want.

    There's a SLEW of 26 tires out there and that's going to be the case for many years to come. New tire molds? That depends on how many 26 bikes continue to exist and need tires. I've bought 3 new tire designs post 27.5 take over: magic mary, dhr2, Michelin wild rocker2.

    Simply put, when those that want 26, give up and buy 27.5, 26 will be dead. I ride what I want, not what my LBS wants to sell. Kona 167 will be my next bike even though my local Kona dealer isn't stocking it. That's their loss, not mine! Buy what you want and you'll have a measurable effect on the market unlike voicing your opinion on forums. Talk is cheap, put your money where your mouth is.

  122. #122
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    Quote Originally Posted by half_man_half_scab View Post
    "No statistical difference" gets trumped by "real world difference." ??!

    This person is not a scientist, but is surely an idiot.
    Between one race team and another, between one championship football team and another, between one tennis player and another, it is possible to have no statistical difference and still have one come up as champion. The guy could have expressed his statement better, but I get what he is trying to say. The preference for the 29er, is pretty much an opinion, as he didn't deliver any numbers.

  123. #123
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    Quote Originally Posted by slimat99 View Post
    Just because your LBS doesn't stock 26 shouldn't stop anyone from buying what they want.
    But it will. Most people are sheep who buy what the shops and magazines tell them they should. And right now they are telling them that 29ers are the best thing ever. Guys like you or I who know what we want and will hunt for it are the minority.

    Quote Originally Posted by bing! View Post
    Between one tennis player and another, it is possible to have no statistical difference and still have one come up as champion.
    Sorry, but I think the guy was just full of shengus. People with lab coats can't admit they have no clue.

    Reminds me. At the time when my wife was expecting our first sprog she had been suffering from ME for several years. We were in the hospital, just at the start of labour, when a young female doctor, white coat, lots of pens, came by. I asked her if she knew how the labour might effect my wife's ME. This is what the puffed up little toy doctor said, word for word:

    "Well, in my experience these things can either get worse, get better or stay the same."

    It was all my wife and I could do not to burst out laughing! What a Womble.

  124. #124
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    Quote Originally Posted by ColinL View Post
    WTB has apparently decided to not produce new tire models in 26", instead offering only 27.5 and 29. I don't know if anyone else has started this yet, or discontinued production of existing 26" models, but it's coming.

    26" tires and wheels won't get to be as scarce as 650B once was, say 8 years ago, but it is absolutely declining.
    I respectfully disagree, while some companies, such as WTB may be stupid enough to discontinue 26" tires, those with at least some business sense will continue. 26" MTB's have been sold the world over for the better part of 3 decades. There are literally millions of 26" bikes still running around the world today vs tens of thousands 650b's, if that many. And how many people replace their bike every 2-3 years? I'm guessing less than 5%. MTBR, Pinkbike, and every other forum only represents a small fraction of the actual world wide MTB community. WTB should fire whoever made that call.

  125. #125
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    Quote Originally Posted by Mr Pig View Post
    But it will. Most people are sheep who buy what the shops and magazines tell them they should. And right now they are telling them that 29ers are the best thing ever. Guys like you or I who know what we want and will hunt for it are the minority.



    Sorry, but I think the guy was just full of shengus. People with lab coats can't admit they have no clue.

    Reminds me. At the time when my wife was expecting our first sprog she had been suffering from ME for several years. We were in the hospital, just at the start of labour, when a young female doctor, white coat, lots of pens, came by. I asked her if she knew how the labour might effect my wife's ME. This is what the puffed up little toy doctor said, word for word:

    "Well, in my experience these things can either get worse, get better or stay the same."

    It was all my wife and I could do not to burst out laughing! What a Womble.
    Actually she gave a great answer because even though we like to pretend we know almost everything about the human body the truth is we don't. Not by a long shot. Even the very best doctors in the world can only make an educated guess and will admit they can't be 100% sure because every body is different and will react different and we still have so much more to learn. A drinking buddy of mine works for CERN and he will be the first to admit that science just graduated from kindergarten. Don't forget we are still in the first grade. A doctor who knows for certain is the one I would avoid the most, and I work in one of the worlds most expensive private medical clinic.

    Sorry off topic.

  126. #126
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    Quote Originally Posted by Swissam View Post
    Actually she gave a great answer..
    No, she had no idea but couldn't admit it.

    I do agree with your assessment of science and the medical profession. If you think scientists have all the answers you know zero about science.

  127. #127
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    Quote Originally Posted by chowdapilot View Post
    There are instances in other sports where the hybrid design loses. One that comes to mind is surfing. Take the fun board for instance. Yes, there are many great fun boards (I even have one) but in the end nothing truly paddles like a long board or rips like a short board. Fun boards try to take the best of both, but many end up with the worst of both. Not saying this is true for 27.5 but something to consider. That said, who really cares, this is why I rock a 7'8" fun board when everyone else is on an 11' plank.
    that was kind of my impression of 650B. It does nothing well. 29ers roll great, but lack "flickabiltiy". 26 are great to flick around, but don't roll as well. I have not found the 650B I have been on to be as flickable. However, at the time I was riding them, there were not any 26 versions of the same bike available.
    Crusin' on a fake duck with a Sharks jersey on and a pig's tail in my fork.

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  128. #128
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    Quote Originally Posted by ColinL View Post
    WTB has apparently decided to not produce new tire models in 26", instead offering only 27.5 and 29. I don't know if anyone else has started this yet, or discontinued production of existing 26" models, but it's coming.

    26" tires and wheels won't get to be as scarce as 650B once was, say 8 years ago, but it is absolutely declining.
    Make sure you don't buy anything WTB anymore. Vote with your wallet.

    Specialized has done the same with a new tire. So, it's looks like they are jumping in to the "boycot 26ers" barrel too.

    So, don't buy Specialized either. It's pretty much the only way we can vote.

    Bikeradar's relatively thorough study on wheel size comparison.-spec-slaugh.jpg
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  129. #129
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    Kinda funny to boycott Specialized for wheel size. They were about the last of the major makers to move into 650b. They had done testing and not found favorable results. Specialized held off selling any and publicly criticized the wheel size for a couple of years.

    Then late last summer, they reluctantly offered the Stumpy FSR and soon after the Enduro in 650b. They felt direct pressure because the public had started to switch gears from 26 & 29 to the new tweener size.

    However, these are cobbled together bikes with front triangles from 29er and 26er wheels sizes respectively because they needed to get something to market quickly. I also suspect they did this to test the waters to see if it is worth it for them to invest in tooling to make dedicated 650b frames with "proper" geometry.

  130. #130
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    I can't really blame a company for not making tires that aren't going to sell. Molds are expensive and you need to have a pretty good volume of sales to pay back your investment.

    Plus, these guys were used to moving say, 10,000 tires a month, and all of a sudden its going to be more like 1000. So their 6 month inventory of tires just turned in to 5 years inventory.

    Even if they aren't making new tires, the old stock will be around for a long time. By the time those inventories are depleted, they can reevaluate how to best supply the 26" market. In a couple of years, who knows how big the 26" tire demand will be.

  131. #131
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    They should try doing the test offroad. Honestly though I wonder how much the gearing has to do with it.
    Killing it with close inspection.

  132. #132
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    Quote Originally Posted by smilinsteve View Post
    I can't really blame a company for not making tires that aren't going to sell. Molds are expensive and you need to have a pretty good volume of sales to pay back your investment.

    Plus, these guys were used to moving say, 10,000 tires a month, and all of a sudden its going to be more like 1000. So their 6 month inventory of tires just turned in to 5 years inventory.

    Even if they aren't making new tires, the old stock will be around for a long time. By the time those inventories are depleted, they can reevaluate how to best supply the 26" market. In a couple of years, who knows how big the 26" tire demand will be.
    So to finish my thought, instead of boycotting the companies not making new 26" tires, you should buy tires from those companies to deplete their inventories, with the hope that that causes them to consider new production.

  133. #133
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    Some thoughts:

    He says several times that the differences are "not statistically different from zero". As soon as he says that, everything else where he says one is better or worse is subjective.

    That means that the variance of data for each wheelsize is so large that a 19 second difference isn't significant. That means that there is a huge variance in the data.

    On average, 29er riders were 19 seconds faster than 27.5er riders. This could mean that one or two riders was way faster on 29 than all the other

    Here is a hypothetical table where the average difference is 19 seconds, but realistically, there is no difference between the two
    27.5 29
    Sec Sec Diff
    rider 1 901 901 0
    rider 2 905 906 1
    rider 3 906 906 0
    rider 4 858 890 32
    rider 5 890 889 -1
    rider 6 903 902 -1
    rider 7 907 908 1
    rider 8 950 850 -100
    rider 9 850 850 0
    rider 10 960 840 -120
    Average Difference -18.8 (29er ~19 seconds faster)
    Statistical difference: none (T test, assuming equal variances)
    Granted, this isn't necessarily what happened, but the data must have had such a large variance for 19 seconds over a 15 minute course to be insignificant.


    He talks about "practical" vs "statistical" differences. As a scientist, he should know better. The real world can often make differences appear significant, that is why you use statistics. He keeps saying that mathematically there is no difference, but then says one is quickest, best...but that's not how statistics work.


    Here's how they should design a good study

    Create 1 mile course with lots of variations
    Get more than 30 riders
    Randomly assign a wheelsize to each rider for lap 1. Record lap times

    Randomly assign different wheelsize for lap 2. Record lap times

    Have rider complete 3rd lap on last wheelsize. Record lap times.

    At this point you have 90 data points to compare, but we're not done.

    Get the same 30 riders together the next weekend. Repeat the experiment.

    Repeat the experiment for ten weekends, so you have 900 data points to compare. Do not compare lap times, compare lap time differences between different wheelsizes.

    Give me the statistical results like this:

    Average difference for the following times:
    26-27.5
    26-29
    27.5-29

    Standard deviation for the same groups above.

    Is each difference statistically different from zero?

  134. #134
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    Quote Originally Posted by dompedro3 View Post
    Here's how they should design a good study

    Create 1 mile course with lots of variations
    Get more than 30 riders
    Randomly assign a wheelsize to each rider for lap 1. Record lap times

    Randomly assign different wheelsize for lap 2. Record lap times

    Have rider complete 3rd lap on last wheelsize. Record lap times.

    At this point you have 90 data points to compare, but we're not done.

    Get the same 30 riders together the next weekend. Repeat the experiment.

    Repeat the experiment for ten weekends, so you have 900 data points to compare. Do not compare lap times, compare lap time differences between different wheelsizes.

    Give me the statistical results like this:

    Average difference for the following times:
    26-27.5
    26-29
    27.5-29

    Standard deviation for the same groups above.

    Is each difference statistically different from zero?
    this is how I would do it, using the same riders doing ten laps per bike on different occasions, starts to dilute any outstanding / terrible days and laps.

    They probably ran out of funds / time to be able to do it this way, or participants (of quality) willing to give up so much time.

  135. #135
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    And if the 29er is fastest, then followed by 26 then 27, what do we do?

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    Pick the wheel size that matches your riding style and local terrain, ride the hell out of it with a smile on your face and forget about speed.

  137. #137
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    Quote Originally Posted by chowdapilot View Post
    And if the 29er is fastest, then followed by 26 then 27, what do we do?
    Come up with a hypothesis why the wheel size between the two is the worst and test that.

    Break up the components of the trail (climb, descend, flat, turns, ect) and see what the differences are in there.

    Usually with a correlation like this you would expect some kind of parabolic relation. With the best at size X and it gets worse as you get larger and smaller. If 27.5 is worse than both 26 and 29 it means its M shaped which would be pretty odd and would need something to explain that.

    If that really was the case for the overall lap time correlation. I'd start by breaking up the climb, descend, turns, flat rolling sections and seeing the correlation between wheel size and times for those.

  138. #138
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    Quote Originally Posted by charging_rhinos View Post
    Not a single helmet visor. Not a single (hidden brake finger-induced) brown pow-ing of a corner. Not a single whew-bro dogpile of affirmation after each lap.

    This study's data is untrustworthy at best.

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    Sounds right!

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