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  1. #1
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    Modern Geometry-Any negatives???

    So with bikes getting steeper STA, slacker HTA & less offset forks, are there any negatives, or will everyone go this way? I guess also are there applications where this would not be beneficial, say XC racing? I haven't ridden one of these newer geometry bikes but would like to. Great to see the continuing evolution but at what point is to much too much?

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    Quote Originally Posted by Unbrockenchain View Post
    So with bikes getting steeper STA, slacker HTA & less offset forks, are there any negatives, or will everyone go this way? I guess also are there applications where this would not be beneficial, say XC racing? I haven't ridden one of these newer geometry bikes but would like to. Great to see the continuing evolution but at what point is to much too much?
    Too many variables for any concrete assessments, but you can read in plenty of places on mtbr that not everyone loves it.

    I do, so long as the "modern geometry" isn't too extreme.

    You're going to have to ride a bunch of bikes in a bunch of situations before you can decide for yourself what you think, and whether you think any manufacturers are taking it too far.

  3. #3
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    I agree with Harold, you are going to have to try some bikes. For the trails I ride, it flat out works. My buddy was looking at a Ripmo, and the shop was recommending a medium, while I suggested he try a large with a shorter stem. He loved the large, which is pretty modern at his height. Another friend, about the same height liked the old school fit of the medium with a longer 50mm stem. I have bumped up against my maximum reach, so I know how far to go, and rode short bike for decades, and won't go back. I may be 60, but am not stuck in the past and will try new things.
    I got some bad ideas in my head.

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    A lot of the new bikes have a very low bottom bracket that can lead to loads of pedal strikes and big problems on technical climbs.

    Other than that, I'd say it's all aces.
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    Modern Geometry-Any negatives???

    I personally love how my XL Ripmo climbs and descends with much more confidence than my Niner Jet 9 did, however I don’t feel like I’ve dialed in the fit yet. The steep ST puts your pedals more underneath you rather than in front of the saddle, which takes getting used to, and uses different muscles. Your legs are pushing down rather than forward and down. You don’t realize this until a ride or two on familiar trails. It’s easier to get up technical terrain, but initially it’s more fatiguing until you train those muscles.

    The saddle forward/ bottom bracket back position in my case also pushes more of my weight forward, and I’m currently experimenting with riser bars, stems and different grips because I’m experiencing pressure on my hands and wrists that I never experienced before.

    As said, pedal strikes were more noticeable too, but in my case my shock had an internal leak that was covered under warranty, and a volume spacer was added so I would not have to pump it up so far above the recommended pressure to achieve proper sag.

    Edit: As mentioned in the next post, the long wheel base does also take some getting used to. It works well in most places here on the West coast, but there are tight switchbacks that were never a problem on the Niner that I just can’t steer around tight enough to avoid going off the outside edge. This shortfall is compensated for when plowing through (not weaving around) rock gardens, which the longer wheelbase and slack HT does much better.

    It is not perfect, but it is a lot more fun to ride and confidence inspiring.

    As others have said, you really just need to ride a few, and if you can demo your top choices more than once, I would recommend it. Things came to light on the Ripmo after the third ride that I hadn’t noticed or understood on the initial few rides.


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  6. #6
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    Its going to come down to body mechanics and where you live. Some of the new bikes are really long in the wheel base so if you ride lets say in the NE compared to out West the longer end of wheel base might not work as well. One of the reason I didn't go with the new Firebird was it was a long bike and I ride tight twisty trails in NE, compared to the old firebird that was compact in comparison. Other than that the new geo is amazing and so much more centered. No more constant seat adjustment for finding the sweet spot.
    Funny my dad and most of his riding buddies are in there late 60's and early 70's. My dad is the only one that rides modern geo and the rest of the guys refuse to try it because they don't want to put in the time to adjust to long and low. It will be interesting to see when he finishes building his Offering if any of them will change their tune.
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    Only one...

    Taken 5 years for everyone else to cotton onto it ^^

    Kona had it back in 2014 with their Process line...

    Which means they were planning it in 2011.

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    I don't personally like to ride rolling flatter trails with a STA more than 75° but 77° is great for climbing.

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    coming from someone who prefers a rigid singlespeed, I think the reach on new bikes has gotten a bit ridiculous. I am very keen on optimizing the distance from my feet to my hands so I can wrangle the bike over terrain using my whole body. if the distance is too far, the bike is harder to control. if it's too short, it's cramped. I fit squarely in the "medium" size category for any sizing scheme, but some "medium" sized frame are so enormous that I would need to use an upside-down riser bar and the shortest stem possible to make the bike manageable.

    with a long fork and long reach, this distance gets so long that you have to rely on big tires and lots of supple suspension to just plow through stuff. for my riding style, that's boring. I guess "mountain biking culture as gone astray." if I wanted to do that, i'd put a motor on my bike, and then i'd be a poseur on a motorbike.

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    Coming off of "traditional" XC hardtails, I prefer modern geo with one exception- BB's that are too low.

    The rest is great. Short chainstays, long reach, short stems, steep STA's, slacker HTA's- all good for me. Even on my "modern XC" geo bikes.

    To me they're more fun all around and I think there are few or no compromises for where and how I ride. (though I admit at first I was reluctant to give it a try. My preconceived notions and worries were quickly dismissed)
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    if the reach would increase somewhat in proportion to the shortening of the stem, I would be all for it, but blasting the reach out 70mm and then putting a fork that shoots the stack up another 30mm means the "same size" bike just feels huge.
    Last edited by mack_turtle; 01-13-2019 at 04:38 PM.

  12. #12
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    For the record none of my bikes have a stem that is shorter than 80mm. Most are 90 ish. That's a lot shorter than the 115mm stem that came stock on my 2011 Jamis Dragon Pro 29er.

    I buy XL's, haven't found one that was too big for me yet.
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  13. #13
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    The new geo is not so great IMO for terrain that is more rolling and flattish. Especially for shorter travel bikes. Where it shines brightest is when you have a bike with a slack HTA and terrain that is steep up, steep down, and not much in between. Riding with a 77* STA on a 100mm bike with a 120mm fork on flatter terrain is a little goofy feeling. A bit like a TT bike.
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    Quote Originally Posted by BmanInTheD View Post
    Riding with a 77* STA on a 100mm bike with a 120mm fork on flatter terrain is a little goofy feeling. A bit like a TT bike.
    what bikes are those?
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  15. #15
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    Quote Originally Posted by mack_turtle View Post
    if the reach would shrink in proportion to the shortening of the stem, I would be all for it, but blasting the reach out 70mm and then putting a fork that shoots the stack up another 30mm means the "same size" bike just feels huge.
    That's going to depend on your body dimensions.

    As a positive ape factor guy, I like my bikes to be longer. Pretty sure that long inseam/short torso tall riders (the ones who used to ride old geo xc bikes with a HUGE saddle-handlebar drop because they had to just to find a frame that fit) are really appreciating bikes with tall stacks, too.

    Also haven't really had any major issues with bb height, either. Every time I climb on a bike with a lower bb, there's an adjustment period, but it doesn't take long for me to reset my attention on pedal position.

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    I really like the modern geo bikes that I've ridden, but in addition to the BB issues that people have mentioned, I'd say that some of the longer, slacker bikes can feel less playful on gentler trails. To give an example: If you read first ride reviews of the new Jeffsy, multiple cite that it climbs AND descends better than the last version, but just isn't quite as playful seeming. Now, I'm not complaining as advances have allowed me to ride one bike on everything from CC to the bike park, but there are some tradeoffs in playfulness.

    That being said, the geo advances have made shorter travel bikes way more capable than before, so if playfulness is your goal, you can size down in travel and still get descending confidence to rival last generations somewhat bigger bikes.

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    Quote Originally Posted by BmanInTheD View Post
    The new geo is not so great IMO for terrain that is more rolling and flattish. Especially for shorter travel bikes. Where it shines brightest is when you have a bike with a slack HTA and terrain that is steep up, steep down, and not much in between.
    I agree on steep seat tubes for flatter terrain. My hardtail has a 75° STA (not super steep) and I still notice more pressure on my hands on flat terrain.



    It's all about selecting the right tool for the job. In really tight terrain a long wheelbase can feel cumbersome (although at 6'5" that's just life). Progressive 29ers like to be leaned and in really slow tight sections where you can't do that the front end wants to understeer. Short chainstays (maybe more trendy than 'progressive') can make a long slack trail bike more playful and maneuverable but also less stable which is why you tend not to see really short stays on enduro bikes. Also, don't buy an enduro bike then complain about pedal strikes during climbs on your techy XC trails. Additionally, anyone complaining about enduro bikes making the trails boring might be right but they're not riding them on the proper terrain.

  18. #18
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    Quote Originally Posted by Harold View Post

    Also haven't really had any major issues with bb height, either. Every time I climb on a bike with a lower bb, there's an adjustment period, but it doesn't take long for me to reset my attention on pedal position.
    I have done a fair amount of bike testing and demo's in recent years. There were a couple of standouts where the low BB was substantial. Two of the most significant were a Plus and Fat bike where low pressure tires caused a significant drop in BB height and caused pedal strikes. These were bikes with 65mm of BB drop.

    My personal bikes are closer to 55mm, except for the Krampus which is 65mm but even with 180mm cranks I have no pedal strike problems.

    I'm curious about your experience on the bikes you've ridden as I get the feeling you get around? What bikes have you tested and how low was the BB?
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  19. #19
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    Quote Originally Posted by *OneSpeed* View Post
    I have done a fair amount of bike testing and demo's in recent years. There were a couple of standouts where the low BB was substantial. Two of the most significant were a Plus and Fat bike where low pressure tires caused a significant drop in BB height and caused pedal strikes. These were bikes with 65mm of BB drop.

    My personal bikes are closer to 55mm, except for the Krampus which is 65mm but even with 180mm cranks I have no pedal strike problems.

    I'm curious about your experience on the bikes you've ridden as I get the feeling you get around? What bikes have you tested and how low was the BB?
    I have done fewer demos in the past couple of years than in years prior. Nothing I have ridden recently has been pushing the limits of long, low, slack all that much. They certainly would have been revolutionary a decade ago, but nowadays, they are more or less typical.

    And as far as "how low" the bb was, I couldn't tell you. I never bothered to look, since the bb height wasn't an issue.

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    I see a lot of guys around here who think they automatically need 900mm bars and 62 degree HA and a low rider bottom bracket. Makes zero sense around here. Where and how you ride matter a lot.
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    I don’t think you’ll see “too extreme” as a consumer, the mfgs weed out the “bad seeds” by using testers and racers.

    If anything, the consumer gets a watered down version of extreme to avoid being “shocked”.

    You can get extreme in your geo now, there are some small companies building really long bikes that are super slack.

    So why haven’t you (the OP) demoed any of these modern geo bikes?

    Quote Originally Posted by Unbrockenchain View Post
    So with bikes getting steeper STA, slacker HTA & less offset forks, are there any negatives, or will everyone go this way? I guess also are there applications where this would not be beneficial, say XC racing? I haven't ridden one of these newer geometry bikes but would like to. Great to see the continuing evolution but at what point is to much too much?
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    Quote Originally Posted by Nurse Ben View Post
    I don’t think you’ll see “too extreme” as a consumer, the mfgs weed out the “bad seeds” by using testers and racers.

    If anything, the consumer gets a watered down version of extreme to avoid being “shocked”.

    You can get extreme in your geo now, there are some small companies building really long bikes that are super slack.

    So why haven’t you (the OP) demoed any of these modern geo bikes?
    Ah too much snow but thanks for suggestion!!

  23. #23
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    Quote Originally Posted by Nurse Ben View Post
    I don’t think you’ll see “too extreme” as a consumer, the mfgs weed out the “bad seeds” by using testers and racers.

    If anything, the consumer gets a watered down version of extreme to avoid being “shocked”.

    You can get extreme in your geo now, there are some small companies building really long bikes that are super slack.

    So why haven’t you (the OP) demoed any of these modern geo bikes?
    I disagree, we will (and are) definitely seeing too-extreme. On the one side, there are the companies that refuse to update their stuff, on their last legs, or selling Taiwan cookie-cutter bikes, and on the other extreme, there are a few companies pushing radical geometry way ahead of what appears to be the norm, trying to ride the "bubble" or be "ahead" of everything, except they'll fall on their face because they took it too far.
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  24. #24
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    430mm Reach For Life, B!tches!

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    Ideally you should shop around your local shops for the bike suited for your trail conditions and riding style.

    The slack style of bike may be cumbersome to you whereas a cross country set up bike could be different and more suited to you.

    I switched from an older XC style bike to a modern geometry bike. At first it was weird, now the old XC bike is weird and I can't think of very many reason why I should have purchased a bike similar to the old one for my riding conditions.

    Until I live in a mostly flat area I'm sure the current geometry is going to suit me pretty darn well.

  26. #26
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    Quote Originally Posted by jeremy3220 View Post
    I agree on steep seat tubes for flatter terrain. My hardtail has a 75° STA (not super steep) and I still notice more pressure on my hands on flat terrain.


    It's all about selecting the right tool for the job.... Progressive 29ers like to be leaned and in really slow tight sections where you can't do that the front end wants to understeer... Additionally, anyone complaining about enduro bikes making the trails boring might be right but they're not riding them on the proper terrain.
    I'll second that.

    Overall bike geo has moved in the right direction and is overall much better - but, you still can't get something for nothing.


    Ideally bike makers release bikes that work well for their intended terrain - rather than simply catering to consumer whims. Look at the recent Pinkbike poll and thread statements on what riders think they need in terms of desired geo.

    https://www.pinkbike.com/news/pinkbi...-favorite.html

    Either people are riding some really outlandish and bizarre terrain, or riders are getting sucked into the "more is better" idea, without really thinking it trough.



    Trails don't _all_ go down as Pinkbike would have you believe. All trails are not buffed out, parky, high speed sidewalks. All downhills are not 45 degree craggy chutes. It is now easier than ever for riders to mislead themselves into thinking they need a longer, slacker bike than they do. Use the right tool for the job. Just because an enduro bike "pedals well" does not mean it's the best tool as a xc-trail bike.

    Newer riders will never get to see how much was "doable" on a xc-trail bike under a skilled pilot.


    Steep seat tube angles, I've found, are a trade off. A steep STA is particularly troublesome for riders who still spend long hours covering a lot of ground on pedally rides. This past season I've gradually nudged the saddle on my trail bike forward on its 74 degree seat tube. Maybe I'm running something like a 75. I got somewhat use to it. It is better on steep smooth climbs. (Though most steep climbing for me is tech and out of the saddle.) The downside is there was a lot more weight on my hands and a lot less power on the pedals. When I went back to my shoulder season gravel/road rig with a 72-73 degree STA I was astonished at how much more power I could put to the pedal - and do it over much longer distances. Hand pressure, pain, and numbness went away. My feet were pedaling in more of a circular, scraping fashion, instead of constant downward pressure (likely trying to keep my hands unweighted) and foot numbness went away.

    The stuff I get to routinely ride most certainly has far more steep climbing than most places I travel to ride - so a steep STA would definitely be useful, but I find the tradeoff not worth it. When I want to spend 3 hours on the bike, a lot of that time is still on rolling terrain, a steep STA is a problem.

    If riders would realize they don't need 6" of saggy travel out back for most trail riding steep STAs wouldn't be such a "thing".


    Super slack head tube angles seem to affect slow speed tech climbing. Trialsy moves and picking ones way up steep, ledgy, rocky, off-camber climbs can be affected by slack HTAs. Wheel flop can easily throw you off course when picking your way at slow speeds. Shorter stems also negatively impact this. Maybe this might be something that can be fixed with shorter offset forks? We'll see how that one plays out.


    Bike geo is way better today, but it is definitely not a one size fits all affair. It is still about picking the right tool for the job.

    Enduro style riding and bikes sure do benefit from very steep STAs and super slack HTAs. Trail bikes don't.
    Last edited by Miker J; 01-14-2019 at 02:24 PM.

  27. #27
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    Quote Originally Posted by Miker J View Post
    Overall bike geo has moved in the right direction and is overall much better - but, you still can't get something for nothing.
    Agree. There is no getting around the fact that slacker HTAs, longer FCs, (and possibly longer chainstays to balance the whole thing out) increase the wheelbase. Puts the rider "in" the bike, but is a negative in tight terrain. Or any skinny that isn't straight.

    The Vorsprung video Jayem posted in the Pole thread covered a lot of concepts that I was aware of, but had not seen discussed.

    I can say from experience that the needs of a heavy clyde are different than a lighter, shorter rider. Both of my friends are skinnier and shorter than me. We ride the same model of bike, me XL, they have Mediums. I have to be more active on the bike then they do to ride the same terrain. That goes for endos and looping. On the plus side, I can loft / wheelie / manual much better than they can.

    If I got one of these new mega-bikes that Pole has created, I suspect I could sit and grind over more terrain like my buddies do. But don't really want that for Texas. Might be nice in the mountains.

    I've been playing with bike geo for a long time, and currently am running an HTA of 65.9 on my Banshee Prime. I have a backup Prime running a 68.3 HTA. Even on XCish trails, I surprisingly don't get much out of the steeper HTA. It's marginally better on very tight singletrack, and that's about it.

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    Quote Originally Posted by Jayem View Post
    I disagree, we will (and are) definitely seeing too-extreme.
    Same.
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    Modern Geometry-Any negatives???

    Quote Originally Posted by isleblue65 View Post
    ..ship..
    I personally love how my XL Ripmo
    ..snip..

    Your legs are pushing down rather than forward and down. You don’t realize this until a ride or two on familiar trails. It’s easier to get up technical terrain, but initially it’s more fatiguing until you train those muscles.

    The saddle forward/ bottom bracket back position in my case also pushes more of my weight forward, and I’m currently experimenting with riser bars, stems and different grips because I’m experiencing pressure on my hands and wrists that I never experienced before.

    ..snip..
    I have demo’ed a medium Ibis Ripmo for 3 days on my local trails. So I feel I got to know the bike fairly well, awesome bike. I have been riding a medium Mojo3 for the last 2 years, also awesome (super quick, chuck-able and fun 26 lbs). I am looking at the Ripmo for the more downhill and chunky capabilities, which it has over the Mojo3. The Ripmo is more work on the climbs and flats, I switched the tires to 2.6 Maxxis Forekasters front and rear and this made a huge difference. It saved 3/4 of a lb of rotating weight (29lbs total) and really woke the Ripmo up (still not as quick as the Mojo3).

    I have had the same hand pain/pressure in my palms of my hand riding the Ripmo as you experience.

    The setup on my Mojo3 puts the grips level with the saddle and the reach to the grips is 1/4” longer (with a 60 mm -6 deg. stem and 780 bar) than the Ripmo. The Ripmo demo setup was 55mm stem 0 deg and 800 bars. The grips were ~3/4 to 1” above the saddle. This setup feels short seated.

    I am trying to figure out what setup on
    the Ripmo will alleviate the hand pressure. I am 5’-8” and feel the medium is the correct size and I like the short wheelbase (1190mm). I am thinking a lowerise 780bar, 55-60mm -6 deg. stem.

    @isleblue65 Let me know what you figure out.

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    A lot of smart guys giving solid opinions in this thread.

    I'll put in my 2 cents as well, I ride a L Foxy 29 which most consider pretty modern.

    Love the overall fit of the bike. I do everything better, but the largest improvement is in my technical climbing. It also turns just amazing. The part of the fit that makes the most sense for me, is the 490 Reach. All bikes need this for standing up, imo.

    Here are the things I've noticed to be aware of on my next purchase:

    1) The Foxy has sort of a medium height BB, and I absolutely do not want any lower of a BB. Even though I'm on 170mm cranks, I could not deal with any lower.

    2) I have ran it with the stock 66 degree head-tube angle, and also with the included 65 degree headset adaptor. I don't want any more slack that 65, and frankly on a long bike, 65 might be a little much, as the length already provides a lot of stability. If I was building my dream bike this Foxy would be very close, but I'd order it with a 65.3 degree head-tube angle as a nice compromise.

    3) I have played with and managed to alter my effective seat tube angle thru seat position and the -1 headset spacer. And I'm torn on these fashionable really steep seat tube angles. At about 75 degrees I 100% preferred it over my effective 73 degree previous Yeti 5.5. But now that I have it at an effective 76 degree, well it's awesome on the steep climbs but it's lacking everywhere else. I can tell when that just sliding my butt back an inch or two, that I have more power. I keep riding it set at 76 degrees cause I'd like to believe that the testers that ride tons of bikes, know what they are talking about when they claim steeper is better. It's TBD for me. But there is no denying I am climbing way better on this bike overall.

    The Foxy 29 is as close to perfection for me and I don't desire any more extreme numbers at this time. In fact, I think the new Yetis might have taken it to far (headtube and seat tube, and BB) and suspect geo will go back a bit on the next generation.

  31. #31
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    Quote Originally Posted by Miker J View Post


    Trails don't _all_ go down as Pinkbike would have you believe. All trails are not buffed out, parky, high speed sidewalks. All downhills are not 45 degree craggy chutes. It is now easier than ever for riders to mislead themselves into thinking they need a longer, slacker bike than they do. Use the right tool for the job. Just because an enduro bike "pedals well" does not mean it's the best tool for as a xc-trail bike.

    Heh, that reminds me of the 2hrs of scree-hiking it took to get to the top of this mountain. So worth it, but still you don't see the hours of hike-a-bike in the 5 minute videos on youtube, or if you do it's a 5-second slo-mo clip. Not the hours of constant swearing we were doing... lol

    Modern Geometry-Any negatives???-g0189099.jpg

    Modern Geometry-Any negatives???-g0147373.jpg

    Modern Geometry-Any negatives???-gopr7201.jpg

    This is definitely one of the realizations I've had in the last 10 or so years, that I have to "live on the bike". Going downhill is good and fun, but you don't spend anywhere near a majority of the time doing that and if the bike isn't comfortable to climb and be on otherwise, you're going to be hating it the majority of the time. Choosing tiny bikes that squeeze you down just really screwed us over for years on end and the manufacturers didn't help by making the larger sizes really goofy with super high top-tubes and super-long headtubes. Luckily that changed and now you take a much smaller "hit" for getting a big-enough frame as far as maneuverability. I'd rather have my bike reasonably balanced and climbing up 20+% grades and making the switchbacks is part of the ride.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  32. #32
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    Quote Originally Posted by Miker J View Post
    ...Trails don't _all_ go down as Pinkbike would have you believe. All trails are not buffed out, parky, high speed sidewalks. All downhills are not 45 degree craggy chutes. It is now easier than ever for riders to mislead themselves into thinking they need a longer, slacker bike than they do. Use the right tool for the job. Just because an enduro bike "pedals well" does not mean it's the best tool for as a xc-trail bike....
    Totally.
    Do the math.

  33. #33
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    There’s only a few carbon FS bikes that truly have a top tube long enough for me, but once I found them, I really appreciate it! They handle around corners so much better without understeer.

    Only a couple of years ago, a stem shorter than 100mm on a bike would have been considered “not pro.”

    I do think that bottom brackets are a tad too low for rock gardens at times, but I get what they’re going for.

    Ultimately I think modern geometry is just what Gary Fisher and the crew were after on Repack in the 1970s, big bars, short stem, fat tires. We just had to unlearn all the misnomers of 1990s roadie-driven XC. I shudder when I see a “classic” Klein up for auction.


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    I got some bad ideas in my head.

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    Interesting thread. I'm getting ready to demo a few of the new bikes. I am fairly concerned about the pedal strike issue, as we have a lot of pretty heavy duty rock gardens where I ride.

    I was passing by a guy on his new Stumpjumper yesterday, and asked him how he liked it. He shouted back "pedal strikes!". Hmm...

    Although I realize a bike is more than numbers on a page, I'm thinking the right bike for me (and where I ride) is a large with 130-140mm travel, 66-67 deg HA, 1200 mm WB, 460 mm reach, 13.5" BB, 75 deg SA, 28-29 lbs.

    Semi-modern?

  36. #36
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    When it comes to the whole pedal-strike / BB height question, having some sort of flip-chip or adjustable dropout in the rear is a great feature. I've noticed more bikes with this lately. My Banshees have this, and I would not give it up.

    There is also the offset shock-bushing option, although it's hard to get much change from that.

  37. #37
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    Quote Originally Posted by BmanInTheD View Post
    The new geo is not so great IMO for terrain that is more rolling and flattish. Especially for shorter travel bikes. Where it shines brightest is when you have a bike with a slack HTA and terrain that is steep up, steep down, and not much in between. Riding with a 77* STA on a 100mm bike with a 120mm fork on flatter terrain is a little goofy feeling. A bit like a TT bike.
    THIS. I foresee more setback dropper posts coming to market to slacken that seat angle for the flatland riders. A 25mm setback is about the difference btw a 77 and 74 deg sta.

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    Quote Originally Posted by Schulze View Post
    THIS. I foresee more setback dropper posts coming to market to slacken that seat angle for the flatland riders. A 25mm setback is about the difference btw a 77 and 74 deg sta.
    I love my 9 point 8 dropper. Can easily change the head to set back one for flat days.

  39. #39
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    Quote Originally Posted by Miker J View Post
    Steep seat tube angles, I've found, are a trade off. A steep STA is particularly troublesome for riders who still spend long hours covering a lot of ground on pedally rides. ... When I went back to my shoulder season gravel/road rig with a 72-73 degree STA I was astonished at how much more power I could put to the pedal - and do it over much longer distances. ... When I want to spend 3 hours on the bike, a lot of that time is still on rolling terrain, a steep STA is a problem.

    ...

    Super slack head tube angles seem to affect slow speed tech climbing. ... Wheel flop can easily throw you off course when picking your way at slow speeds.
    I agree with so much of what Miker J wrote.

    (1) Steep seat tube angles put me in the wrong position for long rides -- definitely faster and more power if I have my "roadie" position relative to the bottom bracket for all but the steepest climbs.
    (2) If the hill is steep, I can either slide up to the nose of the saddle for that pitch or stand. No prolonged climb is so steep that I don't find it better to be seated with a setback post on a 74° STA (or less). Really steep uphill pitches are always short enough such that they can be ridden on the nose of the saddle if rear wheel traction is an issue (effectively steepening the STA for that short duration) or done standing.
    (3) Slack head tube angles (68° on a 29er is slack to me) have the front end wandering up steep techy climbs and under steer on slower speed twisty trails.
    (4) And after years of largely not worrying overly about pedal strikes, now I do with my "newish" geometry bike. It's a Rocky Mountain with their Ride 9 variable geometry system and I run it with the highest bottom bracket setting precisely to avoid pedal strikes.

    I posit that much of the enthusiasm for "Modern Geometry" is at least in part misplaced, with some of the improvement in handling do to improvement in frame materials (carbon?) and designs that lead to stiff front triangles and to stiffer/burlier forks providing the stability at speed that so many people enjoy. YMMV.
    "The plural of anecdote is not data." -- Attributed to various people in a variety of forms, but always worth remembering...

  40. #40
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    Quote Originally Posted by chomxxo View Post
    I shudder when I see a “classic” Klein up for auction.


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    I Ride WAY faster on my new bikes with new Geo, but I was able to bunny hop around 30” high on my Klein Adroit... which I can’t do anymore... but that is probably because I am old now!
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    Quote Originally Posted by JACKL View Post
    When it comes to the whole pedal-strike / BB height question, having some sort of flip-chip or adjustable dropout in the rear is a great feature. I've noticed more bikes with this lately. My Banshees have this, and I would not give it up.

    There is also the offset shock-bushing option, although it's hard to get much change from that.
    I honestly wish more bikes came with these. There isnt a right BB height for everywhere ,but we all have preferences.

  42. #42
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    With the steeper STA I find the rear suspension to work more freely in really rock terrain even if the trail is flat.

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    I'm glad to see there are lots of other riders that don't think a super-steep STA is a panacea for everyone on every trail.
    Yeti SB100
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  44. #44
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    Quote Originally Posted by BmanInTheD View Post
    I'm glad to see there are lots of other riders that don't think a super-steep STA is a panacea for everyone on every trail.
    It works quite well for me, but I would never extrapolate my positive experience to anyone else.
    Riding Washington State singletrack since 1986

  45. #45
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    If you have not adjusted your style to the newer geometry, that would prevent you from taking advantage of the advancements, hence you would likely see change as negative.

    Don't blame the "geometry/messenger".

    I am just messing with you to make a point, BUT, saying a 68 deg HTA is slack kinda puts you in the old school category... I'd consider that an XC HTA.

    So I'm not saying all changes are good, but I suspect that since most mfgs have adopted aspects of the new geo and racers as well as seasoned skilled riders are adopting the new geo, it probably makes sense that the changes are for the good.

    Change is hard, fighting change makes it harder, so maybe just embrace it and learn how to make it yours.

    No obligations to like or even embrace change, just saying it might work out better for you in the end...

    Quote Originally Posted by Ptor View Post
    I agree with so much of what Miker J wrote.

    (1) Steep seat tube angles put me in the wrong position for long rides -- definitely faster and more power if I have my "roadie" position relative to the bottom bracket for all but the steepest climbs.
    (2) If the hill is steep, I can either slide up to the nose of the saddle for that pitch or stand. No prolonged climb is so steep that I don't find it better to be seated with a setback post on a 74° STA (or less). Really steep uphill pitches are always short enough such that they can be ridden on the nose of the saddle if rear wheel traction is an issue (effectively steepening the STA for that short duration) or done standing.
    (3) Slack head tube angles (68° on a 29er is slack to me) have the front end wandering up steep techy climbs and under steer on slower speed twisty trails.
    (4) And after years of largely not worrying overly about pedal strikes, now I do with my "newish" geometry bike. It's a Rocky Mountain with their Ride 9 variable geometry system and I run it with the highest bottom bracket setting precisely to avoid pedal strikes.

    I posit that much of the enthusiasm for "Modern Geometry" is at least in part misplaced, with some of the improvement in handling do to improvement in frame materials (carbon?) and designs that lead to stiff front triangles and to stiffer/burlier forks providing the stability at speed that so many people enjoy. YMMV.
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  46. #46
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    Not really understanding the steep seat angle issue because the saddle is going to be set into my ideal KOPS position regardless. However I'm not sure if I understand why the industry would adopt steeper STAs, since that would tend to make a bike even longer with an already-lengthened new-school front end.

    I'd imagine they'd want to tuck the rear wheel under a bit and flay out the swingarms for better suspension performance. But again, I haven't let it affect me with two new-school bikes, a Fuel EX and Tallboy CC.

    I don't think that slack head angles with a shorter stem make the front end wander; that's old-school rhetoric. Besides making immediate steering adjustments more immediate (helpful on switchbacks), it makes the front end weighted farther ahead of you, which means you don't have to lean so far forward.

    I don't see how a slacker bike could ever be considered to understeer. If you've ever wrapped yourself up in a corner with a 120mm stem at 71* HA, you know all about understeer.

    My Fuel EX was ridiculous about pedal strikes, especially with the long cranks I put on it, but I couldn't bear to flip the chip, it just handled so much better with a slacker geometry and lower bottom bracket. You can give those advantages up, at a cost...

    The key, the really big deal of all of this I think, is the longer top tubes and resultant shorter stem. This gives people, finally, the proper size of bike. You could take away all the other advantages, and this would be the biggest one.

  47. #47
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    I worry some about the steep seat tube angle for midwest riding where there is a lot more flat than ups and downs.

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    Quote Originally Posted by bdundee View Post
    I worry some about the steep seat tube angle for midwest riding where there is a lot more flat than ups and downs.
    Are they putting steep STA's on bikes for that kind of riding?

    edit: and I mean short travel 29/27.5's under 120mm.

  49. #49
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    Quote Originally Posted by Dale-Calgary View Post
    Are they putting steep STA's on bikes for that kind of riding?

    edit: and I mean short travel 29/27.5's under 120mm.
    I have no idea, flat-ish doesn't necessarily mean no need for more suspension.

    edit: and I mean just because we don't spend a lot of time going up or down doesn't mean there is not chunk or big drops.

  50. #50
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    Quote Originally Posted by bdundee View Post
    I have no idea, flat-ish doesn't necessarily mean no need for more suspension.

    edit: and I mean just because we don't spend a lot of time going up or down doesn't mean there is not chunk or big drops.
    True,

  51. #51
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    Quote Originally Posted by RSAmerica View Post
    The Ripmo is more work on the climbs and flats, I switched the tires to 2.6 Maxxis Forekasters front and rear and this made a huge difference. It saved 3/4 of a lb of rotating weight (29lbs total) and really woke the Ripmo up (still not as quick as the Mojo3).

    I agree. The DHF Minion and DHR Aggressor are great for hooking up in a lot of conditions, but very very slow rolling.

    I have had the same hand pain/pressure in my palms of my hand riding the Ripmo as you experience.

    The setup on my Mojo3 puts the grips level with the saddle and the reach to the grips is 1/4” longer (with a 60 mm -6 deg. stem and 780 bar) than the Ripmo. The Ripmo demo setup was 55mm stem 0 deg and 800 bars. The grips were ~3/4 to 1” above the saddle. This setup feels short seated.

    I am trying to figure out what setup on
    the Ripmo will alleviate the hand pressure. I am 5’-8” and feel the medium is the correct size and I like the short wheelbase (1190mm). I am thinking a lowerise 780bar, 55-60mm -6 deg. stem.

    @isleblue65 Let me know what you figure out.
    I definitely will keep you posted. I may document all of the things I've tried in a separate post, as I know several new geo bike owners who struggle with some of the same issues.

    I've tried different stems with different rises, different bars with sweep and rise variability, different widths, different grips and different saddles.

    I am narrowing it down to what feels right in most of these areas, but I'm still working on tying it all together. I was very surprised that bar height and stem length made no difference for me regarding hand pressure. I have gone from 1" lower than saddle height to 2" above, zero degree rise up to 35 degree stems from 50 to 100mm long and still experienced hand pressure.

    I noticed that my wrists are not in line with my arms (they are turned inward slightly). Going from a rather narrow cross country 710mm bar to 800 with the same 9 degree sweep could be the culprit.

    On paper, and anatomically, it does not make sense that your bars would not increase in sweep as they get wider. If you hold your hands in front of you, keeping your elbows in a natural position and move your arms apart, your hands move in an arc, not a straight line, yet most handlebars do not match that arc in the degrees of sweep. When aggressively riding downhill, the elbows out position is more natural, which keeps wrists aligned, but most people spend more time climbing or flat riding where elbows are down, and this is where I'm feeling the most discomfort in hands and wrists. Ergon GE1 grips are my latest addition, and those have helped noticeably with palm pressure, but they do not help my wrist angle.

    I have SQLab 30X (12 degree sweep, 780mm wide) bars coming tomorrow, and I'm especially excited to try these out. I'm hopeful that the unconventional sweep of these bars brings me proper ergonomic alignment for most of the riding I do with minimal compromise while downhilling.

    Modern Geometry-Any negatives???-sqlab-bars.jpg
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  52. #52
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    Quote Originally Posted by mack_turtle View Post
    I think the reach on new bikes has gotten a bit ridiculous... ...with a long fork and long reach, this distance gets so long that you have to rely on big tires and lots of supple suspension to just plow through stuff. for my riding style, that's boring.
    This is how I feel, too. The new geo really takes a lot of the fun out of it for me. I don't need to be the fastest person on the trails. I just want to feel like I'm going fast and maximize the terrain that makes it mountain biking.

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    I pedal strike on my full suspension, but mostly when I'm squishing the suspension in a dip or something.
    I don't just accidentally ride around looking for something to rotate my pedal onto.

    I have yet to pedal strike the Chameleon. The full suspension has a higher bottom bracket spec height than the Chameleon, but once you sag the suspension the FSR is a bit lower. Again, I don't pedal strike aside from a once in a while suspension bounce scenario.

    I can't imagine having the manufacturers raise the BB another 1/2".
    Granted, I have no idea how a bike with a taller, or lower BB affects ride characteristics.
    I get the concept that lower BB's are easier to corner, etc, but I haven't ridden 2 extreme settings. Even my 2000 Stumpjumper HT has a near same BB height. I never had pedal strikes on that either.

  54. #54
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    Quote Originally Posted by Nurse Ben View Post
    If you have not adjusted your style to the newer geometry, that would prevent you from taking advantage of the advancements, hence you would likely see change as negative.

    Don't blame the "geometry/messenger".

    I am just messing with you to make a point, BUT, saying a 68 deg HTA is slack kinda puts you in the old school category... I'd consider that an XC HTA.

    So I'm not saying all changes are good, but I suspect that since most mfgs have adopted aspects of the new geo and racers as well as seasoned skilled riders are adopting the new geo, it probably makes sense that the changes are for the good.

    Change is hard, fighting change makes it harder, so maybe just embrace it and learn how to make it yours.

    No obligations to like or even embrace change, just saying it might work out better for you in the end...
    Why should I change my personal preferences just because the industry wants to sell more bikes and endubros can't ride a flow trail with less than 160mm travel and geometry that erases the essence of mountain biking?

  55. #55
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    Quote Originally Posted by Nurse Ben View Post
    If you have not adjusted your style to the newer geometry, that would prevent you from taking advantage of the advancements, hence you would likely see change as negative.

    Don't blame the "geometry/messenger".

    I am just messing with you to make a point, BUT, saying a 68 deg HTA is slack kinda puts you in the old school category... I'd consider that an XC HTA.

    So I'm not saying all changes are good, but I suspect that since most mfgs have adopted aspects of the new geo and racers as well as seasoned skilled riders are adopting the new geo, it probably makes sense that the changes are for the good.

    Change is hard, fighting change makes it harder, so maybe just embrace it and learn how to make it yours.

    No obligations to like or even embrace change, just saying it might work out better for you in the end...
    Well, when the vast majority of trails out there are firmly in the XC realm, maybe an “XC HTA” is the right tool for the job?




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  56. #56
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    Quote Originally Posted by mountainbiker24 View Post
    Why should I change my personal preferences just because the industry wants to sell more bikes and endubros can't ride a flow trail with less than 160mm travel and geometry that erases the essence of mountain biking?
    Nobody said you have to ride an enduro bike on xc trails. But even more recent xc bikes are adopting some modern geo elements.

    What people are saying is that different bike geo in general requires adjustments to your riding technique. As a rider, you need to be flexible enough to adjust to that. Bikes are not going to be the same for all time and even if you try to keep the same bike, you will EVENTUALLY have to replace it and adapt to riding something a little different.

    You might still love your old bike you can't ride anymore, and have lots of fond memories of riding it, but life will suck if you cannot adapt to and enjoy riding the new one, too.

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  57. #57
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    Quote Originally Posted by isleblue65 View Post
    I definitely will keep you posted. I may document all of the things I've tried in a separate post, as I know several new geo bike owners who struggle with some of the same issues.

    I've tried different stems with different rises, different bars with sweep and rise variability, different widths, different grips and different saddles.

    I am narrowing it down to what feels right in most of these areas, but I'm still working on tying it all together. I was very surprised that bar height and stem length made no difference for me regarding hand pressure. I have gone from 1" lower than saddle height to 2" above, zero degree rise up to 35 degree stems from 50 to 100mm long and still experienced hand pressure.

    I noticed that my wrists are not in line with my arms (they are turned inward slightly). Going from a rather narrow cross country 710mm bar to 800 with the same 9 degree sweep could be the culprit.

    On paper, and anatomically, it does not make sense that your bars would not increase in sweep as they get wider. If you hold your hands in front of you, keeping your elbows in a natural position and move your arms apart, your hands move in an arc, not a straight line, yet most handlebars do not match that arc in the degrees of sweep. When aggressively riding downhill, the elbows out position is more natural, which keeps wrists aligned, but most people spend more time climbing or flat riding where elbows are down, and this is where I'm feeling the most discomfort in hands and wrists. Ergon GE1 grips are my latest addition, and those have helped noticeably with palm pressure, but they do not help my wrist angle.

    I have SQLab 30X (12 degree sweep, 780mm wide) bars coming tomorrow, and I'm especially excited to try these out. I'm hopeful that the unconventional sweep of these bars brings me proper ergonomic alignment for most of the riding I do with minimal compromise while downhilling.

    Click image for larger version. 

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    If you want unconventional...
    https://youtu.be/Ndt8Di_TjJE

  58. #58
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    One thing to consider; it's a lot easier to run a setback post and/or a longer fork on a bike with a STA that is steeper than you prefer than it is to achieve a steeper STA with one that is too slack....

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    Quote Originally Posted by oldsklrdr View Post
    If you want unconventional...
    https://youtu.be/Ndt8Di_TjJE
    Bikepackers have embraced high sweep bars (15 to 25 degree) for a long time. That’s not practical for all-mountain, at least not without multiple hand positioning with brake and shift lever access - similar to road bike handlebars.

    More than 16 degrees sweep starts to strain your wrists in the opposite direction zero sweep bars do while climbing - when you drop your post and push your body back.

    Interesting concept though.


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  60. #60
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    Quote Originally Posted by chomxxo View Post
    I don't see how a slacker bike could ever be considered to understeer.
    Because less weight on the front tire means less traction.

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    You are missing the point. It's not about you and it's not about the industry wanting to sell more bikes; though it would be silly to think they want to sell fewer bikes

    These changes, like anything, are advancing the way that bikes handle. Just because you don't like it doesn't mean it doesn't work.

    So you have a choice, either adapt or don't.

    Most people would say that adaptation and flexibility are essential for advancing your abilities, but it's your life and there is no obligation for you adopt new habits.

    The classic change that comes to my mind during the winter season is shaped skis: There was a time when a ski was straight, ie no or minimal sidecut, so the ski had to be arced to turn. Now we have shaped skis, the ski should still be arced for optimal function, but now the ski will turn simply by being laid over on it's side.

    Some people still prefer straight skis. Some people prefer riding rigid bikes.

    Judging goes both ways, so perhaps this discussion is not you bailiwick?

    Quote Originally Posted by mountainbiker24 View Post
    Why should I change my personal preferences just because the industry wants to sell more bikes and endubros can't ride a flow trail with less than 160mm travel and geometry that erases the essence of mountain biking?
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  62. #62
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    Umm, not really, anglesets work both ways, you can also adjust feel with a change in offset.

    Some Mfgs shoot for the middle, then you have a choice, but clearly a bike with a 63 deg HTA is not meant for or intended to satisfy people who want a steeper HTA

    Quote Originally Posted by David R View Post
    One thing to consider; it's a lot easier to run a setback post and/or a longer fork on a bike with a STA that is steeper than you prefer than it is to achieve a steeper STA with one that is too slack....
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  63. #63
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    Quote Originally Posted by jeremy3220 View Post
    Because less weight on the front tire means less traction.
    That's oversteer. By point of reference, Sports cars that are front-engined tend to understeer because most of their weight is on the front. As a mountain biker, like a race car driver, we know that a skid is much better controlled on the rear.

  64. #64
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    I really notice the flop of the slacker front end especially when trying to ride hands off. My ol' Hardrock was way, way more stable. Getting on a 26er "NORBA" feels really strange now. The fact mine is a tandem makes it even stranger. I've considered just giving it the wider bars and shorter stem. I like them.

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    Quote Originally Posted by Nurse Ben View Post
    You are missing the point. It's not about you and it's not about the industry wanting to sell more bikes; though it would be silly to think they want to sell fewer bikes

    These changes, like anything, are advancing the way that bikes handle. Just because you don't like it doesn't mean it doesn't work.

    So you have a choice, either adapt or don't.

    Most people would say that adaptation and flexibility are essential for advancing your abilities, but it's your life and there is no obligation for you adopt new habits.

    The classic change that comes to my mind during the winter season is shaped skis: There was a time when a ski was straight, ie no or minimal sidecut, so the ski had to be arced to turn. Now we have shaped skis, the ski should still be arced for optimal function, but now the ski will turn simply by being laid over on it's side.

    Some people still prefer straight skis. Some people prefer riding rigid bikes.

    Judging goes both ways, so perhaps this discussion is not you bailiwick?
    I'm a sucker and just trust the industry.

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    Quote Originally Posted by chomxxo View Post
    That's oversteer. By point of reference, Sports cars that are front-engined tend to understeer because most of their weight is on the front. As a mountain biker, like a race car driver, we know that a skid is much better controlled on the rear.
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    Quote Originally Posted by chomxxo View Post
    That's oversteer. By point of reference, Sports cars that are front-engined tend to understeer because most of their weight is on the front. As a mountain biker, like a race car driver, we know that a skid is much better controlled on the rear.
    The words are the same regardless of cars or bikes. Understeer is when the front gets loose (or pushes), oversteer is when the rear gets loose. It happens from either not enough weight or downforce* on one end to provide the necessary grip, or from too much cornering force that overwhelms the amount of available grip.

    All of us non-pro riders are probably most likely to have understeer from not weighting the front enough due to technique. Slack front ends could make that a bit worse, but longer reach is now counteracting that to put the riders weight more forward.

    Old bikes with a steep HTA were more endo prone and required a lot more body movement to counteract this. But without a dropper post you couldn't get low and centered so you had to get back behind the seat. I had a lot to unlearn and relearn when I got a dropper post!


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    I think part of the issue folks have with new geometry is the assumption that because they're adapted, comfortable, etc on their current set up that means that it is also optimal.

    While for some, this may be true, but for others it very likely isn't. If they would give something different (which is also supposed to be better) enough time they would adapt to that and exceed their performance from their old norm.

    Analogy, once upon a time I gotten pretty decent for my weight class with squats and deadlifts. I had no complaints about my form, no pain, injuries etc. Started training at a different gym and the owner, asked me if I would be willing to try a different form. He said for the first few weeks, or maybe months, I would be working with lower weight but it would pay off once I got the new form down and my body adjusted. He was right and I exceeded my old maxes easily.

    Same idea here, just because what you have works, doesn't mean you won't be better on something else given the chance.

    Also, understeer and oversteer are defined by which end looses traction first, weighting tendencies may influence how it manifests but doesn't define what's happening. If the front wheel looses traction first and pushes, that's under steer, rear wheel first is over steer.

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    Quote Originally Posted by chomxxo View Post
    That's oversteer. By point of reference, Sports cars that are front-engined tend to understeer because most of their weight is on the front. As a mountain biker, like a race car driver, we know that a skid is much better controlled on the rear.
    The front losing traction is understeer (the actual turning angle is less than the steering angle). It's easy to confuse weight and mass in this case. For instance trail braking works by shifting weight onto the front tires but the mass distribution doesn't change much. Mass distribution as it relates to understeer vs oversteer is primarily a consideration of steady state cornering. This is easy to see by going to a gravel lot; hang of the back of the bike as far as possible then try to turn. The front will understeer.

  70. #70
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    I recently bought a bike with a 55mm increase in reach/100mm increase in wheelbase vs. the bike i'd been riding for the past 3 years and found it much easier to adjust than I expected based on the comments here (previous, similar threads). It's not like I had to relearn how to ride; it's more of a subtle weight shift forward compared to what I used to do in order to keep my weight centered. It doesn't take the fun out of riding flatter, tight twisty trails at lower speeds. I feel safer and more confident in steep terrain and at higher speeds. It's easier to keep the front wheel planted on steep climbs without shifting my weight forward. I really haven't found anything to dislike about the new bike/new geometry so far.
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    Quote Originally Posted by chomxxo View Post
    That's oversteer. By point of reference, Sports cars that are front-engined tend to understeer because most of their weight is on the front. As a mountain biker, like a race car driver, we know that a skid is much better controlled on the rear.
    You have that completely backwards.

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    Quote Originally Posted by matt.s67 View Post
    You have that completely backwards.
    Nope, I totally do not. Y'all are wrong on this. I'm right.

    An old school mountain bike has a too-short top tube, too steep head tube, and a too-long stem. Therefore too much weight is biased forward. That induces understeer (like a Subaru WRX)

    A slacker geometry with longer top tube and slacker geometry puts more weight on the back end, like an drift car, and carving through corners is more controllable.

    Hopefully you flow like a mid-engined car through corners, as that's the best scenario, but get it right.


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    Quote Originally Posted by chomxxo View Post
    Nope, I totally do not. Y'all are wrong on this. I'm right.

    An old school mountain bike has a too-short top tube, too steep head tube, and a too-long stem. Therefore too much weight is biased forward. That induces understeer (like a Subaru WRX)

    A slacker geometry with longer top tube and slacker geometry puts more weight on the back end, like an drift car, and carving through corners is more controllable.

    Hopefully you flow like a mid-engined car through corners, as that's the best scenario, but get it right.


    https://jalopnik.com/the-idiots-guid...-to-1795389460
    More weight on the front = more front wheel traction. If you have more front wheel traction, and the car (or bike) loses traction in a turn, the rear will break loose, inducing oversteer. Understeer would be if the rear is weighted, and the front breaks loose. I don't need a Jalopnik guide, I've been racing cars for 15 years.

    "Carving through corners" is not more controllable with less weight on the front end on a mountain bike. It causes front wheel wash outs, also known as understeer (not oversteer as you seem to think). And yes, you still have it backwards.

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    Quote Originally Posted by chomxxo View Post
    Nope, I totally do not. Y'all are wrong on this. I'm right.

    An old school mountain bike has a too-short top tube, too steep head tube, and a too-long stem. Therefore too much weight is biased forward. That induces understeer (like a Subaru WRX)

    A slacker geometry with longer top tube and slacker geometry puts more weight on the back end, like an drift car, and carving through corners is more controllable.

    Hopefully you flow like a mid-engined car through corners, as that's the best scenario, but get it right.


    https://jalopnik.com/the-idiots-guid...-to-1795389460
    So you can't understand the article you told us to read? You have it totally backwards. Do we need to get the GG guys in here to convince you?

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    Quote Originally Posted by chomxxo View Post
    That's oversteer. By point of reference, Sports cars that are front-engined tend to understeer because most of their weight is on the front. As a mountain biker, like a race car driver, we know that a skid is much better controlled on the rear.
    Understeer is sliding the front Oversteer is sliding the back.

  76. #76
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    Quote Originally Posted by boomn View Post
    All of us non-pro riders are probably most likely to have understeer from not weighting the front enough due to technique. Slack front ends could make that a bit worse, but longer reach is now counteracting that to put the riders weight more forward.
    Longer slacker front ends paired with short rear ends place more weight on the rear of the bike. Longer reach decreased front end grip by lengthening front center while your overall body position, reach+stem stays relatively the same.

    Quote Originally Posted by chomxxo View Post
    An old school mountain bike has a too-short top tube, too steep head tube, and a too-long stem. Therefore too much weight is biased forward. That induces understeer (like a Subaru WRX)

    A slacker geometry with longer top tube and slacker geometry puts more weight on the back end, like an drift car, and carving through corners is more controllable.
    More weight = more grip. Grip balance has a lot to do with overall setup along with weight balance. Race car suspension doesn't directly transfer to bikes.

    Old school geometry has more front end grip and less rear, or Oversteer.
    New bikes with long and slack geometry have problems with front end grip, or understeer.

    Being very tall and riding XXL points this out and most manufactures use the same rear end. I have spent years on bikes that are too small and have taken a very keen interest in bike geometry.

    I also used to build race cars in collage with a focus on suspension setup.
    Making shit harder than it needs to be isn't awesome, it's just...harder.

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    The GG guys, awesome

    Quote Originally Posted by kiotae View Post
    So you can't understand the article you told us to read? You have it totally backwards. Do we need to get the GG guys in here to convince you?
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    Better yet, you ride a lot of bikes, on a lot of different trails, and find what you like

    I'm pretty sure all those engineers know something, certainly more than me, at least when it comes to bike design.

    So yeah, you look at what they're offering, you try new things, you push your limits, and maybe you learn something in the process.

    These threads are so damn funny, as if our complaints mean anything to mfgs... they're looking at sales and race results, and they're listening to their people in the industry and their vendors.

    This place gets a little pinkbikesque in the winter...

    Quote Originally Posted by Dale-Calgary View Post
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    Quote Originally Posted by chomxxo View Post
    Nope, I totally do not. Y'all are wrong on this. I'm right.

    An old school mountain bike has a too-short top tube, too steep head tube, and a too-long stem. Therefore too much weight is biased forward. That induces understeer (like a Subaru WRX)

    A slacker geometry with longer top tube and slacker geometry puts more weight on the back end, like an drift car, and carving through corners is more controllable.

    Hopefully you flow like a mid-engined car through corners, as that's the best scenario, but get it right.


    https://jalopnik.com/the-idiots-guid...-to-1795389460
    You're confusing car mass distribution with weight loading on bike tires.

  80. #80
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    More weight doesn't mean more grip. Grip is determined by coefficient of friction between two surfaces. Tires work on both static friction, and dynamic friction, as they are rolling, but static friction is the kind you may be most familiar with. You have to consider tire load sensitivity, slip angles, and the surface tension too.

    To minimize traction loss, generally, it's wise to help keep the load relatively centralized, balanced, and consistent. Shifting weight to be more forward and rear, side to side, increasing/decreasing the load on the tires tends to affect the static friction and surface tension. Think of the many times you got through low traction areas by just keeping things straight and kept speed consistent--turning and acceleration/deceleration in such sections tended to not happened like expected and threw you off balance.

    chromxxo's post is accurate, and he didn't specify any 4-wheel specific physics that didn't cross over to bicycles. You guys are misinterpreting it. Mid-engine is like having a rider that is centered, rather than one that's hunched forward nor hanging back. chromxxo's conclusion is a bit biased though, putting the slacker and longer top tube bike in a positive light, at expense of the steep HA and short top tube bike. Bikes can be too slack and long too (too rearward biased). One difference is that riders should be able to adapt to the bike being too rearward or forward, while a heavier vehicle can't. Would be simpler and easier to ride if a rider had to compensate/adapt less, but the spartan culture of bike racing dislikes such "cheating", unless everyone has it.

    Taller folks who ride XL+ are more likely to be reluctant to ride bikes that are too raked out, especially small wheeled bikes. They might be more open to bikes with longer CS or steep HA.

    Shorter folks who ride smaller sizes are more likely to notice bikes being too front heavy, and will gravitate towards bikes that are more stretched out in front, and extra short in rear, such as long travel bikes.

    Engineers have a lot of specialized knowledge, but big bike brands aren't engineers. They're big organizations out there to commercialize bikes that will sell for profit, targeting markets that don't know better. Emphasis on the last part. What if we did know better? The big brands could have their goons instill doubt and fear to give themselves time to redesign and catch up...

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    oh my God, you guys, you know better than this. Oversteer is when you slide backward into the tree

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    Quote Originally Posted by isleblue65 View Post
    I definitely will keep you posted. I may document all of the things I've tried in a separate post, as I know several new geo bike owners who struggle with some of the same issues.

    I've tried different stems with different rises, different bars with sweep and rise variability, different widths, different grips and different saddles.

    I am narrowing it down to what feels right in most of these areas, but I'm still working on tying it all together. I was very surprised that bar height and stem length made no difference for me regarding hand pressure. I have gone from 1" lower than saddle height to 2" above, zero degree rise up to 35 degree stems from 50 to 100mm long and still experienced hand pressure.

    I noticed that my wrists are not in line with my arms (they are turned inward slightly). Going from a rather narrow cross country 710mm bar to 800 with the same 9 degree sweep could be the culprit.

    On paper, and anatomically, it does not make sense that your bars would not increase in sweep as they get wider. If you hold your hands in front of you, keeping your elbows in a natural position and move your arms apart, your hands move in an arc, not a straight line, yet most handlebars do not match that arc in the degrees of sweep. When aggressively riding downhill, the elbows out position is more natural, which keeps wrists aligned, but most people spend more time climbing or flat riding where elbows are down, and this is where I'm feeling the most discomfort in hands and wrists. Ergon GE1 grips are my latest addition, and those have helped noticeably with palm pressure, but they do not help my wrist angle.

    I have SQLab 30X (12 degree sweep, 780mm wide) bars coming tomorrow, and I'm especially excited to try these out. I'm hopeful that the unconventional sweep of these bars brings me proper ergonomic alignment for most of the riding I do with minimal compromise while downhilling.

    Click image for larger version. 

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    Biggest factor in hand pressure is seat tilt.

    Tilt your saddle up. But, then you get pressure on "other parts". To fix that raise your bars and that will change your torso and "pelvic tilt, and relieve pressure on the nether regions.

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    Quote Originally Posted by jeremy3220 View Post
    I agree on steep seat tubes for flatter terrain. My hardtail has a 75° STA (not super steep) and I still notice more pressure on my hands on flat terrain.
    Curious, what hard tail are you riding. 75 degrees is nice.
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    Modern Geometry-Any negatives???

    Quote Originally Posted by Miker J View Post
    Biggest factor in hand pressure is seat tilt.

    Tilt your saddle up. But, then you get pressure on "other parts". To fix that raise your bars and that will change your torso and "pelvic tilt, and relieve pressure on the nether regions.
    I generally agree with you, but in the case of new fangled geometry, where the bottom bracket is directly under the saddle instead of just in front of it, tilting the front of the saddle up is not necessarily the fix. That’s the cheapest and first thing I experimented with.

    My saddles have always been flat, and I incrementally tilted mine up until it looked like a BMX bike with the nose of the saddle in the air. Aside from being totally numb and uncomfortable, it surprisingly didn’t reduce much pressure off my hands. Nor did combining saddle tilt with ridiculous looking 35 degree stems that raised my riser bars well above the saddle.

    Saddle back on the rails helped more than all of that (moving BB forward relative to saddle). Grips helped a bit, and I’m hoping the 12 degree sweep bars close the deal. I’ll report back.


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    Quote Originally Posted by isleblue65 View Post
    I generally agree with you, but in the case of new fangled geometry, where the bottom bracket is directly under the saddle instead of just in front of it, tilting the front of the saddle up is not necessarily the fix. That’s the cheapest and first thing I experimented with.

    My saddles have always been flat, and I incrementally tilted mine up until it looked like a BMX bike with the nose of the saddle in the air. Aside from being totally numb and uncomfortable, it surprisingly didn’t reduce much pressure off my hands. Nor did combining saddle tilt with ridiculous looking 35 degree stems that raised my riser bars well above the saddle.

    Saddle back on the rails helped more than all of that (moving BB forward relative to saddle). Grips helped a bit, and I’m hoping the 12 degree sweep bars close the deal. I’ll report back.


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    If a new dropper post is in your budget. You can get a 9 point 8 for 300.00 with a set back post. Tilt and higher bars can help but i found i needed the seat back on long peddly rides.

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    I don't know about that, my tree issues involve falling into them head on or sideways.

    I'm thinking it's the Ents.

    Quote Originally Posted by Darth Lefty View Post
    oh my God, you guys, you know better than this. Oversteer is when you slide backward into the tree
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    @isleblue6 Your upper body weight is most likely the source of the hand pressure. Its weight is supported between your contact points (grips, seat, pedals).

    You have a variety of solutions/options, to transfer weight off your hands. The main solution is to adjust the angle of your back so it's less angled/hunched forward. The more angled forward it is, the more of your upper body weight is supported by your hands, as your back can only transfer so much of that weight to your lower body.

    IMO, you should aim for a tall A-frame shape, with your back and arms, with the hips, shoulders, and hands being the end points. This position should make it easier to pedal with a steeper STA as well. You'll appreciate the better balance of support when your back gets exhausted and, as a bonus, you will be more naturally scanning further up ahead as your head won't be naturally angled to stare at the front wheel.

    I generally think that larger sizes have stack heights that are too low, resulting in grip heights being too low below the hips. The steeper STA bringing the saddle height even higher doesn't help. Having the stem clamped on top of 30+mm of spacers (including the volcano-shaped headset upper caps) leads to a nervous feeling, since it's less stiff.

    If you're trying to get this taller A-frame position from raising your grips, from a riser stem and bar, I'd like to hear how well it works out. I'd expect it to feels like being in a SUV or truck, as opposed to something like a Miata.

    I suggest giving the steep STA some more time for your body to adapt to it, rather than trying to counter it by moving your saddle back more, as studies have suggested that it's more efficient in terms of pedaling power output.

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    Quote Originally Posted by Zerort View Post
    Curious, what hard tail are you riding. 75 degrees is nice.
    Guerrilla Gravity Pedalhead. The actual STA is 75, the effective is 74. With a 36" inseam it feels closer to 75.

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    Quote Originally Posted by ninjichor View Post
    More weight doesn't mean more grip. Grip is determined by coefficient of friction between two surfaces.
    This is wrong and it's easy to see why because you used the word coefficient and that means there's another variable to this equation. That variable is normal force. Weight is a normal force. Aero downforce is a normal force also. Mass increases the weight on the tires which increases friction but also increases cornering load. Tire load sensitivity typically favors having a lower mass vehicle though. On a bike you can manipulate the weight on the tires without much change in mass which is why the car analogy doesn't apply. This is easy to prove via the experiment I mentioned previously.

    Why do you think the front tires of a vehicle have more traction under braking? It's the weight shift to the front. In fact, in some cars that are 'rear heavy' it's easy to oversteer while braking due to lots of front traction but high rear lateral load due to the rear mass.

    You can read The Pneumatic Tire if you're really interested in this stuff. It has all the basic rubber friction info in the chapter by Grosch.

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    Quote Originally Posted by ninjichor View Post
    @isleblue6 Your upper body weight is most likely the source of the hand pressure. Its weight is supported between your contact points (grips, seat, pedals).

    You have a variety of solutions/options, to transfer weight off your hands. The main solution is to adjust the angle of your back so it's less angled/hunched forward. The more angled forward it is, the more of your upper body weight is supported by your hands, as your back can only transfer so much of that weight to your lower body.

    IMO, you should aim for a tall A-frame shape, with your back and arms, with the hips, shoulders, and hands being the end points. This position should make it easier to pedal with a steeper STA as well. You'll appreciate the better balance of support when your back gets exhausted and, as a bonus, you will be more naturally scanning further up ahead as your head won't be naturally angled to stare at the front wheel.

    I generally think that larger sizes have stack heights that are too low, resulting in grip heights being too low below the hips. The steeper STA bringing the saddle height even higher doesn't help. Having the stem clamped on top of 30+mm of spacers (including the volcano-shaped headset upper caps) leads to a nervous feeling, since it's less stiff.

    If you're trying to get this taller A-frame position from raising your grips, from a riser stem and bar, I'd like to hear how well it works out. I'd expect it to feels like being in a SUV or truck, as opposed to something like a Miata.

    I suggest giving the steep STA some more time for your body to adapt to it, rather than trying to counter it by moving your saddle back more, as studies have suggested that it's more efficient in terms of pedaling power output.
    ninjichor, thanks for the thoughtful evaluation. I have considered core strength (or a lack of enough core strength to support my upper body weight) might be part of the equation. However what is confusing to me is that I didn’t experience hand and wrist pressure on my Jet 9, and I was not only more stretched out with a 130mm stem, my handlebar grips were more than an inch lower than saddle height. They were much narrower bars though.

    I’ve already unsuccessfully tried raising my bars with a riser and riser stems on top of it, which both looked ridiculous, but more importantly didn’t make any difference in hand discomfort. I’m back to the zero stem (still with riser bars), and new Ergon GE1 grips, and it feels better than with the riser stems.

    Also, I had a ‘professional’ fitting at the bike shop where I bought it, and they had no clue what to do more than I had already.

    Between component trial and error based on what I already know about riding posture and position, core strengthening, A-frame posture as you mentioned and just getting used to it, I’m confident I’ll get to a place where it’s comfortable.


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    Quote Originally Posted by ninjichor View Post

    chromxxo's post is accurate, and he didn't specify any 4-wheel specific physics that didn't cross over to bicycles. You guys are misinterpreting it. Mid-engine is like having a rider that is centered, rather than one that's hunched forward nor hanging back. chromxxo's conclusion is a bit biased though, putting the slacker and longer top tube bike in a positive light, at expense of the steep HA and short top tube bike. Bikes can be too slack and long too (too rearward biased). One difference is that riders should be able to adapt to the bike being too rearward or forward, while a heavier vehicle can't. Would be simpler and easier to ride if a rider had to compensate/adapt less, but the spartan culture of bike racing dislikes such "cheating", unless everyone has it.

    themselves time to redesign and catch up...
    Thank you. Jesus H, some of you guys act like such pricks, but have no idea what you’re talking about.


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    Quote Originally Posted by chomxxo View Post
    Thank you. Jesus H, some of you guys act like such pricks, but have no idea what you’re talking about.


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    Your quoting of a guy who spouts loads of half-informed bs is telling.

    I don't know the first thing about these overly argumentative technical discussions, but I know from other threads that ninji thinks engineering solves everything (including things it doesn't) so I tune him out as a matter of course.

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    Quote Originally Posted by chomxxo View Post
    Thank you. Jesus H, some of you guys act like such pricks, but have no idea what you’re talking about.
    I'm a tire engineer.

  95. #95
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    Quote Originally Posted by jeremy3220 View Post
    I'm a tire engineer.
    Quiz:

    Take a rider and bike that weighs 200 lbs combined. Give them super strong brakes with super good modulation, able to stop ASAP without skidding.

    Add 50 lbs centralized around the same system CoG point in an otherwise identical setup.

    Will the 50 lb heavier system be able to stop in the same distance, or sooner in comparison, considering braking is not a limiting factor, but traction is? Why is this?

    In other words, does more weight = more grip, or not?

    Hint: see tire load sensitivity.

  96. #96
    Trail Ninja
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    Quote Originally Posted by chomxxo View Post
    Thank you. Jesus H, some of you guys act like such pricks, but have no idea what you’re talking about.


    Sent from my iPhone using Tapatalk
    Being an asshole is more accepted than being scientifically literate on this forum. Seen so much science rejected here, except when parts of it happened to be worded simply enough and was in agreement.

    Sorry, wasn't sure if you were being sarcastic or not, about not noticing the elephant in the room. Got no opinion on modern geo since I haven't tried it, unless you count a Spec Enduro 29, nor have enough information to make a judgment. Just waiting to be convinced, as I'm not ready to spend thousands on incremental improvements.

    Normally, I would just lurk, but I couldn't resist answering the physics questions: the heavier rider will not stop as soon, even if they had stronger brakes, since they'd break traction sooner, meaning they have less grip with more weight. Also, downforce is only for the corners. The race car would risk flipping over otherwise, and would need to go in with less speed, but the downforce allows them to carry more speed in, very important for twisty courses. It's just drag in the straights, but it helps shape airflow to be less turbulent, from vortex shedding and what not.

  97. #97
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    GG Pedalhead, just sold mine, just can’t handle a rigid rear end these days, but man what a great bike! Excellent example modern school geo, functional, not excessive.

    Quote Originally Posted by jeremy3220 View Post
    Guerrilla Gravity Pedalhead. The actual STA is 75, the effective is 74. With a 36" inseam it feels closer to 75.
    XMed GG Smash 29/27+ (Frameset For Sale)
    Lrg Fezzari Signal Peak 29+
    Lrg Pivot Shuttle 27+ (wife's)

  98. #98
    Ride Fast Take Chances :)
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    wow.
    More weight =more grip. Try to push a bike with no rider and it will slide. Now do the same with a rider and it will require far more force.
    More weight means more energy and you have to dissipate that energy and will stop slower.

    Now back to bikes with a fixed weight and variable weight distribution.
    Not being able to load the front wheel of the bike will result in reduced front end traction. The longer a bike becomes the harder it is to load the front. This is especially true with manufactures using the same rear end for all bike sizes.

    New bikes are awesome and I love my Ripmo, but it requires you to ride it slightly different.

    IMO Your saddle should be flat too.
    Making shit harder than it needs to be isn't awesome, it's just...harder.

  99. #99
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    You can claim that the increased weight does come with a gross increase in grip, but the net result is reduced traction, since the grip doesn't increase enough to offset the increased traction demands of the higher weight. If the grip didn't increase at all, then the 50 lb heavier bike+rider wouldn't come anywhere near close to decelerating as quickly or cornering as tightly as the lighter bike/rider.

    Why am I wrong for saying coefficient of friction? Slick surface or slick tire material not matter as much as weight? Put a dumpster on a slope and drop a giant lead weight in it, and the jostling of the weight can break static friction and cause the dumpster to slide down the rest of the slope, despite having extra weight in it. The dynamic friction (sliding) is different from the static friction. Objects at rest and objects in motion...

    If you purposely load the tires, you can break the surface tension of the ground itself. Doing this with the rear wheel in a corner is called a cutty. With the front wheel, a washout. Traction loss from too little, and also too much...

    Why does a wider tire have better grip if it spreads out the load over a larger area, so there's essentially less force on any 1 point between the ground and tire?

    Modern geometry is merely a trend. The longer front ends and shorter rear ends makes 29ers less front-heavy, which is welcome for shorter riders, but taller riders who are on size XL seemingly are getting bothered by the front end being a bit too light for their tastes. Again, too much and too little. IMO, more brands need to adjust chainstay length per size. Glad to see YT is starting to do it.

  100. #100
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    FWIW, I like the newer style geometry bikes. As someone who's riding and racing has a gravity bias, it works for me, but it's now starting to bleed into the trail category which also works for me as I have a trail bike too.

    My Fuel 9.9 with a 140 fork is reasonably long for a large, BB is mega low, the HTA is pretty slack (66 degrees) & the STA (effective) is reasonably steep, although actual it's slack as hell. Being tall, this does push me out over the back of the bike, which is my main complaint about the bike. But, it's light, is short/mid travel & it really rips as a bike. it really can (and has been to be) a one bike for all situations. More recently i've built it back up to be a light trail bike & loving it.

    My bigger bike (Raaw) is huge. 170x160 29er race bike. 500mm reach, 64.5 HA, low BB, 78.2 STA, 450mm CS & ~1300mm wheelbase. it's probably more capable than any DH bike i've ridden (but it's been a few years since i've had one). It's an outright speed machine & makes no excuses for it's intended use. Yet it climbs suprisingly well. I am very central on the bike, the steeper STA puts me in a nice position, and I feel like it will winch up most things.

    I'd like to try something a bit more progressive in a shorter travel, lighter package. I bet it would rip

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