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  1. #1
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    Groupthink, and where it goes wrong.

    I was perusing a different thread in this subforum a few hours ago and came upon this phrase:

    "Lighter and less rolling resistence is always better, there is no exception to this."

    I didn't want to take that thread further off topic, so I started this one. That statement was made in the context of discussing appropriate wheels and tires for any given scenario.

    I started this thread because it occurred to me that I didn't agree with the statement at all. Not even for racer geeks.

    But as I ruminated further on it, I realized that nearly everyone else believes it, accepts it as truth, even if they've never really experimented with anything different to have learned otherwise.

    *-On technical climbs, a heavier wheelset (rims + tires) stays more planted, that is, *maintains better traction* than a lighter wheelset. This is true for dirt as well as snow.

    *-On technical descents, a heavier wheelset is less easily deflected, allowing you to maintain traction and hold your line better. Also true on dirt and snow.

    *-On non-technical trails--climbing, descending, or flattracking--increased wheel (rim + tire) weight gives a flywheel effect. This means that once up to speed you can maintain momentum with less effort. Definitely true on both dirt and snow.

    Every other scenario I can think of is basically a subcategory of the statements above.

    I've been intensely experimenting with different rim widths, tread patterns, tire pressures, and casing thicknesses for the last decade. I stumbled onto the above by accident, when out looking for other answers. But the lessons learned, even by accident, have taught me to stop accepting "facts" as such until they're proven as such.

    I don't own a light XC bike anymore--I don't see the point. Why is that important?

    Because riding will always be faster than walking, not to mention more fun and more rewarding. And I can ride more on a bike with heavier wheels and "slower" tires.

    In case it wasn't clear above, I'm talking about *trail* use, not road of any ilk.

    Discuss?

  2. #2
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  3. #3
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    The correct tire is seldom the lightest.

    Having all of the correct tires is pretty expensive for most people, not to mention how many can't even change a tire to begin with.

  4. #4
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    Lighter and less rolling resistance isn't always better.

    My road bike has extremely light wheels with contact patches the size of dimes. That's low rolling resistance.

    It would be a nightmare off road.

    It seems more correct to say, the lightest wheelset with the lowest rolling resistance appropriate for the situation is best.

    But once you go down that road, my guess is that there are seriously diminishing returns and that experience trumps weight and contact patch.

    Think about it- you weigh 170. your bike weighs 40 pounds. that's a total of 210 pounds. Drop your bike down to 30 pounds and you've dropped 25% off the weight of your bike but only 5% of your total rolling weight, so, it that 5% gonna make that big a difference?

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    Mike I think, at least on the face of it, your implication that heavier is always better is as flawed as the other persons statement that lighter is always better. Even you must draw the line on how heavy you will go for any given condition. I think I read you the other day to say how you are trying hundies in new riding environments because the new ones were light enough to work in that application.
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  6. #6
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    Lighter and less rolling resistence is always better, there is no exception to this."
    This might be somewhat true for road bikes, but not even entirely for them. You have to understand that rolling resistence = traction. I could be more or less convinced that lighter (given strength is the same) is generally better, but traction generally trumps rolling resistance. If this wasn't true every MTB would be running skinny road slicks.

  7. #7
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    Quote Originally Posted by mikesee View Post
    I was perusing a different thread in this subforum a few hours ago and came upon this phrase:

    "Lighter and less rolling resistence is always better, there is no exception to this."

    I didn't want to take that thread further off topic, so I started this one. That statement was made in the context of discussing appropriate wheels and tires for any given scenario.

    I started this thread because it occurred to me that I didn't agree with the statement at all. Not even for racer geeks.

    But as I ruminated further on it, I realized that nearly everyone else believes it, accepts it as truth, even if they've never really experimented with anything different to have learned otherwise.

    *-On technical climbs, a heavier wheelset (rims + tires) stays more planted, that is, *maintains better traction* than a lighter wheelset. This is true for dirt as well as snow.

    *-On technical descents, a heavier wheelset is less easily deflected, allowing you to maintain traction and hold your line better. Also true on dirt and snow.

    *-On non-technical trails--climbing, descending, or flattracking--increased wheel (rim + tire) weight gives a flywheel effect. This means that once up to speed you can maintain momentum with less effort. Definitely true on both dirt and snow.

    Every other scenario I can think of is basically a subcategory of the statements above.

    I've been intensely experimenting with different rim widths, tread patterns, tire pressures, and casing thicknesses for the last decade. I stumbled onto the above by accident, when out looking for other answers. But the lessons learned, even by accident, have taught me to stop accepting "facts" as such until they're proven as such.

    I don't own a light XC bike anymore--I don't see the point. Why is that important?

    Because riding will always be faster than walking, not to mention more fun and more rewarding. And I can ride more on a bike with heavier wheels and "slower" tires.

    In case it wasn't clear above, I'm talking about *trail* use, not road of any ilk.

    Discuss?
    Prove it.

  8. #8
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    I find supple tires provide better traction than ones with very stiff casings. Usually the supple tires also weigh less. Ergo, it seems lighter tires roll better. I am not talking about any gyroscopic effects or deflection, just the quality of the contact patch and how it conforms to terrain features.

    I figure I can aim the tire where I want it, but it's the tire's job to provide the traction.
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  9. #9
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    Quote Originally Posted by sryanak View Post
    Mike I think, at least on the face of it, your implication that heavier is always better is as flawed as the other persons statement that lighter is always better. Even you must draw the line on how heavy you will go for any given condition. I think I read you the other day to say how you are trying hundies in new riding environments because the new ones were light enough to work in that application.
    I didn't write "always", but I did imply "often". And I stand by that.

  10. #10
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    Quote Originally Posted by tscheezy View Post
    I find supple tires provide better traction than ones with very stiff casings. Usually the supple tires also weigh less. Ergo, it seems lighter tires roll better.
    The rooster crowing does not make the sun come up. Although supple tires may have more feel on the trail, I find that running lower pressures tubeless on the same tires results in squirm and less confident traction - in that case I prefer a heavier carcass and a stiffer sidewall and will gladly accept the additional weight. My Racing Ralph 2.4s were supple as anything, but at 26psi would barely keep on track - the Ardents and Purgatories were much more confidence inspiring.
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  11. #11
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    Quote Originally Posted by mikesee View Post
    I didn't write "always", but I did imply "often". And I stand by that.
    "Often" it is then.

    As to the individual points in your thread starter I would offer a couple of points:

    On technical climbs if they are steep enough and I am going very slow, which I do on climbs, my weight on the rear wheel seems to be what keeps it planted maybe the front wheel would wander less if it was heavier.....

    On decents heavier does deflect less....

    I have noticed the flywheel effect for sure and love it when it is all spun up but on twisty turny up and down singletrack that requires very much braking then you have to keep spinning up the flywheel.

    This is starting to decend into splitting hairs on my part so I'll just go riding.
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  12. #12
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    Last edited by bprsnt; 09-23-2012 at 07:30 PM.
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  13. #13
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    I think, as I've said before, it comes down to where you ride, and what you're looking for in that ride.

    Bomber solid, never have to think about it, point and go, middle of nowhere, long hike out type desires? Yep, heavier will reward that group, and they should be entitled to product that works for them

    Seldom more than an hour from home, generally never more than a 20 minute to half hour walk out, lots of climbing, off camber, mud, sand, leaves, wet, rooty, mixed conditions, type riding, often appreciate the lighter weight and more supple ride. These riders also, should have stuff that suits.

    Of course, as others have said, both can be taken to the ridiculous, but a middle ground of light, yet sturdy enough for my situations, and I have no issues, nor do most of the folks I ride with. Of course, anything can happen, period.

    If I found myself being let down by my lighter set ups? I'd change. Seeing as I ride without hassle, why strap extra weight on? My downhills are fast enough to scare me a little now and then, my lungs and legs still burn on the climbs.

    Yep, not seeing the need. However, none of my bikes weighs less than 29 or 30 lbs, with several in the mid 30's...

    All this said? The original statement is ridiculous, there is ALWAYS and exception to an opinion.
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  14. #14
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    Quote Originally Posted by jpettit View Post
    You have to understand that rolling resistence = traction. I could be more or less convinced that lighter (given strength is the same) is generally better, but traction generally trumps rolling resistance.
    How can traction trump rolling resistance when rolling resistance = traction?

  15. #15
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    I finally read the post that Mike quoted to start off this thread and find it interesting that it started off with a reasonable statement that BFL's had their place over presumably "lighter" tires where the trail was soft and then went on to make the somewhat contradictory statement that lighter is always better....I know I'm supposed to be riding.
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  16. #16
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    I would say that lower rolling resistance will always be better *if it doesn't compromise traction*. But it almost always seems to do that, sooo....

    I've always been a fan of big, heavy, knobby tires up front and a lighter tire with less rolling resistance out back. I've always run fr and dh rims on my xc bikes though...

  17. #17
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    Quote Originally Posted by Larry Endomorph View Post
    How can traction trump rolling resistance when rolling resistance = traction?


    Not true. You can have a tire with horrible traction and high rolling resistance just as you could have a tire with incredible traction and low rolling resistance. Tread pattern, rubber compound, casing design, terrain and riding style will have different effects on each quality.

  18. #18
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    Quote Originally Posted by Larry Endomorph View Post
    How can traction trump rolling resistance when rolling resistance = traction?
    I meant it in the context that traction trumps wanted less rolling resistance. We are on the same page, i was just not clear. You should be looking for the tire that offers the traction you need, not the tire that has the lowest rolling resistance.

  19. #19
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    With bike wheels I think it is important to not just think of the energy needed to accelerate heavy parts but rather what happens to that energy after you expended it. I think fat bikes do a great job of preserving that energy and giving it back later. As long as you are not braking a ton and your bike is not wasting/absorbing the energy you put into accelerating it you will get it back. A thoughtfully ridden fat bike can be like a potential energy bank in some ways.

    To test this we need someone with two sets of wheels and a power meter ridden over the same course.

    This thred is similar to what I was trying to say here.
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  20. #20
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    "better" is a bad word

    For me, the problem with these statements is the word "better", it is just to ambiguous.
    I ride heavy, fat, 2.4, tubeless Rubber Queens on my 5" travel bike. They are slower on the climbs then other, lighter tires I've run. But, they allow me to be slower as well, gripping like crazy on technical climbs with little worry of spinning out. So on climbs everyone can make, I'm probably near the end of the group, but on climbs that are more difficult, I am often the only one cleaning them.
    And on the downhills, the confidence they give me is superb!
    So my "better" is clearly different than someone who is interested in faster.
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  21. #21
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    Quote Originally Posted by cbrossman View Post
    So on climbs everyone can make, I'm probably near the end of the group, but on climbs that are more difficult, I am often the only one cleaning them.
    And on the downhills, the confidence they give me is superb!
    This is why I highlighted the word 'technical' in my original post. More mass = more traction, which means that with a heavier setup a given rider stands a higher chance of cleaning something.

    Quote Originally Posted by cbrossman View Post
    So my "better" is clearly different than someone who is interested in faster.
    On roads (dirt, paved, or otherwise), lighter *might* be faster. But on trail, riding is almost always faster than walking. And riding is clearly "better".

    MC

  22. #22
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    You would think that the only proof would be a time clock. But even this would not be total proof. There is always some opposing factor that you cannot duplicate. So I guess mikesee, you are correct in that the dilemma now becomes the perception of what brings you confidence, pleasure, accomplishment, etc.

  23. #23
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    Quote Originally Posted by mikesee View Post
    I didn't write "always", but I did imply "often". And I stand by that.
    I wouldn't have agreed at all with you six months ago, Mike, but now that I have the perspective of a few dozen fast rides on my fatbike with fast riders on "regular" bikes, I do agree that, at times, the momentum and gyroscopic effect of heavier wheels can actually be advantageous. I'll give an example of riding against a headwind on a slight uphill. When you put the power into a pair of Fatbike wheels, you feel the momentum and speed build, even against the wind, and the inertia of the wheels is a good partner to have. Speed isn't easily "blown away".

  24. #24
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    Quote Originally Posted by Jaredbe View Post
    With bike wheels I think it is important to not just think of the energy needed to accelerate heavy parts but rather what happens to that energy after you expended it. I think fat bikes do a great job of preserving that energy and giving it back later. As long as you are not braking a ton and your bike is not wasting/absorbing the energy you put into accelerating it you will get it back. A thoughtfully ridden fat bike can be like a potential energy bank in some ways.

    This thred is similar to what I was trying to say here.
    You are nailing it now...

  25. #25
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    Quote Originally Posted by mikesee View Post
    This is why I highlighted the word 'technical' in my original post. More mass = more traction, which means that with a heavier setup a given rider stands a higher chance of cleaning something.



    On roads (dirt, paved, or otherwise), lighter *might* be faster. But on trail, riding is almost always faster than walking. And riding is clearly "better".

    MC
    Amen brother... It's just all a matter of what you're after. I like riding... And cornering hard.

  26. #26
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    I would love to see the mountain bike community stop using the metric of faster=better for everything because unless you are racing, which some do but even then faster is the end all be all unless you are pro and someone is giving you stuff to race on, it is a meaningless metric.

    I much prefer, akin to MC is saying, to ride my bike in lieu of walking, whether it be through increased traction or increased durability. My bike is the best riding when it is wearing the WTB Dissents but my recent exploration with a wheel 2 pounds heavier in the front but with 3.7inches of soft tractiony traction has made me realize that there can be even more fun.

    I blame magazines for this preoccupation with faster is better.
    Try this: HTFU

  27. #27
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    Schwalbe have done some research into this



    I put a set of Big Apples on my 29er in summer. Freewheeling down a hill in company with other riders on quality road bikes I was having to drag my brakes slightly - much to my surprise. I had fitted the BAs for comfort rather than speed, so now I'm inclined to believe Schwalbe's claims.

    Since trying out the Black Floyds, I'm beginning to wonder whether I should bother with narrower tyres for the road - I'm not likely to spend long at speeds where aerodynamics matter, and I love the speed and security on fast downhills.
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  28. #28
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    drats, I was just about to drill out my 18 spoke carbon hundies.

  29. #29
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    I find that my 27tpi Nate is more gooder than my 120tpi bfl where I ride

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  30. #30
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    Quote Originally Posted by mikesee View Post

    *-On technical climbs, a heavier wheelset (rims + tires) stays more planted, that is, *maintains better traction* than a lighter wheelset. This is true for dirt as well as snow.

    *-On technical descents, a heavier wheelset is less easily deflected, allowing you to maintain traction and hold your line better. Also true on dirt and snow.

    *-On non-technical trails--climbing, descending, or flattracking--increased wheel (rim + tire) weight gives a flywheel effect. This means that once up to speed you can maintain momentum with less effort. Definitely true on both dirt and snow.


    Discuss?
    Greater unsprung weight doesn't necessarily increase traction or increase the ability to hold the line. In fact, on bumpy, technical climbs, greater wheel/tire weight can mean your suspension works less effectively (if you have it), and with or without suspension, can mean that your tires have more inertia driving them away from the ground when you hit a little lip or bump.

    And flywheel effect would be great if energy transmission were 100% efficient. But whatever energy you're storing in your wheels got there from your legs...and you're losing much of it along the way. I'd rather have lighter wheels and fresher legs.

  31. #31
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    I'm going to start carrying all of my camping gear in between the spokes of my wheels. With 170 spacing, there's tons of room down there, and the flywheel effect should get me to Nome what, like 2 days faster than carrying it high on the bike?

  32. #32
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    Your all full of crap...more expensive bikes are faster than less expensive ones. It's a proportional mathematical fact.

  33. #33
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    Quote Originally Posted by sean salach View Post
    I'm going to start carrying all of my camping gear in between the spokes of my wheels. With 170 spacing, there's tons of room down there, and the flywheel effect should get me to Nome what, like 2 days faster than carrying it high on the bike?
    Man I can see a whole new area for "Wheel Pack" designing. If we ran solid discs from the rim edge to the hub flange and then put in a couple of doors......We could carry way more stuff
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  34. #34
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    Quote Originally Posted by sryanak View Post
    Man I can see a whole new area for "Wheel Pack" designing. If we ran solid discs from the rim edge to the hub flange and then put in a couple of doors......We could carry way more stuff
    Something like Rokon's aluminum drum rims:

    Rokon Trail-breaker Motorcycle

    You can carry water, fuel, or whatever, or if you leave them empty they float the bike.

  35. #35
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    Quote Originally Posted by Guipago View Post
    You would think that the only proof would be a time clock. But even this would not be total proof. There is always some opposing factor that you cannot duplicate. So I guess mikesee, you are correct in that the dilemma now becomes the perception of what brings you confidence, pleasure, accomplishment, etc.
    Keep in mind that I'm talking about technical trails--stuff where you either make it, or you don't.

    No clock needed if a heavier wheelset keeps you riding and the lighter wheelset has you cresting the crux on foot.

    I don't often ride tech trails on fat tires, BUT I think my experience with 29" wheels translates, in that a light XC rim and light tubeless tire are never, ever any match for a much heavier "FR" rim and (usually tubed) tire. The only advantage to the lighter setup is that it's easier to carry the whole bike through the tech sections...

  36. #36
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    Quote Originally Posted by buckfiddious View Post
    Lighter and less rolling resistance isn't always better.

    Think about it- you weigh 170. your bike weighs 40 pounds. that's a total of 210 pounds. Drop your bike down to 30 pounds and you've dropped 25% off the weight of your bike but only 5% of your total rolling weight, so, it that 5% gonna make that big a difference?
    I like the thought of lightening up a bike due to the fact that I'm 135lbs soaking wet. A 30 lb bike to a 200 lb guy is a weight ratio of a 20 lb bike to me. I'm not going to spend big dollars to get down to a 20 lb bike, but at my size I'm sure a lighter bike (25 - 26lb mountain bike) will be a benifit to me and increase the "fun factor". My Mukluk 2 was 33 lb when I bought it and It's getting real close to 30 lb now. That is the weight I want for my size.

  37. #37
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    Quote Originally Posted by mikesee View Post
    I was perusing a different thread in this subforum a few hours ago and came upon this phrase:

    "Lighter and less rolling resistence is always better, there is no exception to this."

    But as I ruminated further on it, I realized that nearly everyone else believes it, accepts it as truth, even if they've never really experimented with anything different to have learned otherwise.

    *-On technical climbs, a heavier wheelset (rims + tires) stays more planted, that is, *maintains better traction* than a lighter wheelset. This is true for dirt as well as snow.

    *-On technical descents, a heavier wheelset is less easily deflected, allowing you to maintain traction and hold your line better. Also true on dirt and snow.

    *-On non-technical trails--climbing, descending, or flattracking--increased wheel (rim + tire) weight gives a flywheel effect. This means that once up to speed you can maintain momentum with less effort. Definitely true on both dirt and snow.

    Discuss?
    My disjointed thoughts are that yes, in general you are getting a benefit from the heavier tire/tread, etc in technical conditions. However, there is a point of diminishing returns from a motor (or gearing) standpoint. If my rides are 2/3 climbing, there is a limit to how much weight I can push for how long up however steep a trail. Going down, those same heavy wheelsets will be less nimble. Great for plowing over stuff, crappy for changing direction quickly.

    Ideally, I want wheels/tires that are just barely heavy enough for my application, and no more. I usually err on the side of just a little heavier for durability's sake.

    Upsides to weight: Better traction, less bumping off line, less flats, less rim breakage, holds momentum better.

    Downsides: less nimble, slower to accelerate, and they require more of the motor. I do not know of any suspended type high performance application where unsprung weight is looked at in a positive manner.

    Off road motor bikes wheelsets are very heavy, have incredible traction and capability, are almost impossible to flat, and I would never want to push them on a bike.

    I guess I don't see this as an either/or issue. Weight has its purposes, but on a bike where I am the motor, in the wheels where the weight is unsprung, I will preferentially take the lightest possible weight that suits my needs.
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  38. #38
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    Ah if it were only so simple...

    First, I disagree with the whole premise that "technical" snow climbs and/or descents even exist.

    Also...

    "On non-technical trails--climbing, descending, or flattracking--increased wheel (rim + tire) weight gives a flywheel effect. This means that once up to speed you can maintain momentum with less effort. Definitely true on both dirt and snow."

    ...is simply not true.

    Okay, two identical riders on two identical bikes, with the exception of one having a lighter wheelset, ride from the bottom to the top of a given non-technical climb in the exact same amount of time. Which rider expended less energy? If you pick the heavy wheel rider...I guess we're done here.

    But I'm pretty sure that you (MikeC) aren't saying that the heaviest wheels are always better. I'm pretty sure that you are saying that the lightest *appropriate* combination of rims and tires are always preferable. Having ridden with you a little bit I can see how that is sometimes a pretty beefy combo.

    I've been on rides and in races with wheels that were both too heavy and too light and from my perspective there is little difference.

  39. #39
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    Quote Originally Posted by joatley View Post
    First, I disagree with the whole premise that "technical" snow climbs and/or descents even exist.
    That's because you're usually walking them.

    Tongue in cheek. Kinda...

    There are a few techy bits to ride, on snowpacked trail, around here. You just have to be into that sorta thing.

    Quote Originally Posted by joatley View Post
    "On non-technical trails--climbing, descending, or flattracking--increased wheel (rim + tire) weight gives a flywheel effect. This means that once up to speed you can maintain momentum with less effort. Definitely true on both dirt and snow."

    ...is simply not true.
    Really? To put it in terms you're most familiar with, a disc rear wheel and deep section front don't give you a flywheel effect on the road?

    My experience is that they emphatically do. It was unmistakable to me the few years that I was riding road. Heavier wheels/tires maintain their momentum better.

    I have lots of good examples, but first--are we at least disagreeing about the same thing?

    Quote Originally Posted by joatley View Post
    Okay, two identical riders on two identical bikes, with the exception of one having a lighter wheelset, ride from the bottom to the top of a given non-technical climb in the exact same amount of time. Which rider expended less energy? If you pick the heavy wheel rider...I guess we're done here.
    If you're talking about non-tech like as in buff, smooth, or even road, the guy with the heavier wheels expended more energy.

    As the trail gets more technical, they get closer to even.

    As the trail becomes super technical, the guy with heavier wheels/tires has an unfair advantage--the mass in his wheels is less likely to get deflected or stopped. It also requires more steering input for the heavy wheel rider to change direction--think about the importance of that (in the context of a super tech climb) for a second. The guy with the lighter wheels (even if he's a superstar rider) doesn't have the same amount of wheel mass keeping them planted. They're getting deflected, spinning slightly, and he's fighting the bars as his weight gets moved around on the bike by the slipping of the tires and the deflection of the wheels.

    Guess who dabs first, then walks?

    Next question: Which is faster--walking or riding?



    Truthfully, I don't care which is faster. I'm more interested in what keeps me riding where most are walking.

    Quote Originally Posted by joatley View Post
    But I'm pretty sure that you (MikeC) aren't saying that the heaviest wheels are always better. I'm pretty sure that you are saying that the lightest *appropriate* combination of rims and tires are always preferable. Having ridden with you a little bit I can see how that is sometimes a pretty beefy combo.
    This is a good way to put it. I don't pick out the heaviest stuff deliberately, stick it on my bike, and trust that it's going to be the best compromise. I ride all sorts of wheels and tires, in lots of different conditions, on lots of different bikes. If I'm riding tech trail (and I think the definition of tech trail is probably a cause for confusion for some reading this) and I want to ride the highest possible % of it, you'll find me on a 29" fully with ~700g rims and ~1400g tubed tires. 6 x 6" of travel, total bike weight of about 38lbs, and yes--this is the bike I use most for all-day epics.

    How can I be so sure that's the best combo to be able to ride the highest % of trail? I have a huge amount of tech trail in my 'backyard', and I've been riding it for more than a decade. So have all of my friends. When I was still racing I'd show up to group rides fitter than most and on a lighter bike than most. And I'd be walking the most. It took a LONG time for me to finally "get" that the guys I was riding with were beating me up tech climbs and down, well, everything, because their heavy wheels and tires kept them from getting bounced off line.

    Which brings up yet another rhetorical question: Who's having more fun--the girl cleaning the hard lines, or the girl that bleeds trying, right up until she loses confidence and decides walking is more prudent?

    All I had to do to prove this was start experimenting with heavier rims and tires. No contest--I'm a more competent and confident tech rider when I've got (what most XC geeks would consider appallingly) heavy wheels and tires on my bike.

    All I have to do to start flailing again is stick some XC wheels and light tubeless tires on my bike. Can almost guarantee I'll bleed if I try to ride tech on that sorta setup.

    Thanks for continuing the discussion.

    MC

  40. #40
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    Quote Originally Posted by Andy FitzGibbon View Post
    Something like Rokon's aluminum drum rims:

    Rokon Trail-breaker Motorcycle

    You can carry water, fuel, or whatever, or if you leave them empty they float the bike.
    It's somewhat ironic that you use this as an example, because this was one of my 'aha!' moments.

    I was riding a fat wheeled/fat tired bike on a frozen river in the Idita race years ago. It had been super windy the night before, with the result that there were lots of drifts across the trail. It'd be hardpacked for ~100 yards, then a ~foot high drift across the trail for maybe 8 or 10 feet, then back to hardpacked. It was like this for miles and miles and hours and hours.

    If you just pedaled into the drifts without lifting the front wheel you'd get stopped, now, every time. My 'technique' to get through each drift was to ramp up into a sprint, then manual the front wheel as far as I could through it--kind of what most people do when trying to get across a stream. Half the time it'd work and I'd wobble through, ~half the time the rear wheel would skate sideways and I'd dab, then have to drag the bike through the drift, remount, then get back up to speed before the next drift. Sprinting to get up to speed for the manual was work, but NOWHERE near as hard as re-accelerating from a dead stop.

    As the day went on my success rate increased substantially--I was clearing more like 90% of them. Wondering why (I still had 20 miles to go to the next village--plenty of time to think on it and nothing much else to think about) I started looking for reasons. One thought was that I had just adapted to the conditions--the length of the drifts, consistency of the snow, gear I needed to be in, effort needed to manual, etc... Very possible.

    Another thought was that the drifts might have changed--gotten smaller. I started looking more closely at them, but couldn't really conclude anything either way because I hadn't looked that closely before.

    Then I stopped to take a leak. Set down the bike, walked away for a few, then when I walked back I was fairly well shocked at what I saw: The wheels were solid discs of white. Each time I busted a drift there'd been an explosion of snow, and obviously some of that 'splosion was getting stuck inside the wheel. Hours and hours of that and they had literally built up into discs--you couldn't make out the hubs at all. Naturally, being a card-carrying weight weenie, I took the time to poke and scrape most of the snow out of there before continuing.

    You already know what happened next. Easier to accelerate, much, much harder to actually make it through the drifts.

  41. #41
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    I think a rider that is infused with chocolate chip cookies is a happier rider, whether he is faster or not.

  42. #42
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    My first time out on the Fatback was after a blizzard and we had really deep snow and drifts on my local trail. I could not ride through the deep snow and drifts and thought the snow getting caught in the huge rim surface was stopping me. I did not let it build up into a disc, but i was thinking that is what I needed to slice through the deep stuff. My thought was a Wheelbuilder disc, front and back, like I use on the rear of my triathlon bike. My next thought was that I was crazy, now not so much. Maybe the weight of the wheels and the fact that the snow packed discs cut right through............

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    Quote Originally Posted by mikesee View Post
    If I'm riding tech trail (and I think the definition of tech trail is probably a cause for confusion for some reading this)...
    I think you nailed it with this comment. I look at some of your photos and I think your definition of tech is probably way off of my definition.

    I always assumed that lighter wheels would be better because, on a mountain bike, you accelerate all the time. I mean, it's really rare to maintain a constant speed on singletrack (well, the singletrack I ride). Even consistent pedaling is filled with little accelerations with each pedal stroke (unless you're really smooth and spinning). So, my assumption was that there is too much lost energy with all the accelerations that take place every minute.

    Of course, I own a Mukluk now.

    I'll have to do some back-to-back riding on what I consider to be technical trails with my light bike (26") and my Mukluk. You're arguments are compelling enough to make me reconsider my stance, for sure.

    Thanks.

  44. #44
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    When the winter is over I think I'll have to do my long road loop (140+m) on the Black Floyds.

    I know how long it takes on a normal road bike at my cruising pace, so it would make an interesting comparison.
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  45. #45
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    Question for mikesee and anyone - ever thought of trying a 36er?

    Some thoughts from Walt on the subject.

    I'm interested in trying one.
    Disclaimer: I run Regular Cycles (as of 2016). As a profiteer of the bicycle industry, I am not to be taken very seriously.

  46. #46
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    In the latest edition of Mountainflyer magazine, Mike Mccalla does a great expeiment comparing 26" vs 29" wheels. I would say it's about as scientific as anyone has done to date.

    I think it relates well to this discussion in regards to perceptions of how different tire systems compare in the bike world. It is well worth reading. It does not have the out come probably most would have hope for which makes it all the more compelling to to be weary of perceptions.

    I have been a decent technical rider for many years and have found what is important to me is tires and rims. Two things that I find are most important are rim width and the deadness of a tire. As rim widths have grown, they allow the larger tires to footrint better (wider) and use more of their available tread thus allowing better traction and slowing down their steering like a steering damper, giving more directional control especially at slow speeds.

    The deadness of a tire I find is important too, one that damps well, one that is not boingy. True UST tires, not tubless ready versions have an extra layer of rubber inside that I find increases this damping and makes for a more stable tire and ride, they are heavier but worth it for tehnical and high speed riding like bombing down the Porupine Rim trail.

    There is also the durometer of the rubber to consider too as most tire manufactures have a this point. That makes a difference too but I still find the carcus has alot to do with how well a tire performs.
    Last edited by danaco; 01-26-2012 at 09:34 AM.

  47. #47
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    One of the factors that is important in these discussions is the type of power humans put out. We are not electric motors in a physics 101 class pulling weight up an incline. Fat bikers exert bursts of power in each pedal stroke and between each snow drift or between each roller hill. Although it ultimately takes more energy to move heavier wheels in real world conditions, with the thoughtful bursts of energy followed by recovery that humans produce I find quality fat bike tires and wheels often helpful.
    Last edited by Jaredbe; 01-26-2012 at 09:44 AM.
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    So the reason I'm slow and suck on the technical stuff is that my bike is just not heavy enough? I wish it was true.
    I have no doubt that added weight and stability can improve a bike's overall technical performance, but you need the motor too. An F350 will plow through things that would kill a Fiat, but put the Fiat motor in the truck and it's a total failure. I'm afraid I have a Fiat motor - so the weight burden has an upper limit that I can't ignore.
    When I see an adult on a bicycle, I do not despair for the future of the human race. ~H.G. Wells

  49. #49
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    ^ ^
    It's true that some riders are just inherently better in some applications now matter what equipment is given. I mean, compare and contrast Fabian Cancellara and Andy Schleck. For me, I am a good technical rider and just kill it on the flats, even good on short steeps, but really suffer on long climbs. I love doing endurance events and now I want to be more competitive in them. I believe that the best climbers usually win long races and this is the area I need to improve in, so I finally got a set of reasonably light wheels. But I'm keeping my big tires; I love them. I think that skinny, no-tread XC tires are a complete hindrance unless on a complete non-tech short course (lame). I think you have to even out your efficiencies to you inefficiencies. We'll see if this helps me out come summertime.

  50. #50
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    It is good to have someone like Mikesee around. He's got a veritable fleet of different bikes, doesn't mind trying new things, and thinks about things to figure them out. His solutions may not apply for me, but they have a good basis in thought behind them.

    One major aspect of bicyclists that I've noticed? Conservatism. "This is the way that it is done". A certain lack of interest in new concepts, or a faith-based approach. I know that I started mtb'ing on the advice and knowledge of experienced bikers. I remember that a couple of them actually got frustrated with me because I was listening to what they said, applying it,messing around with it - and making up my own mind if it worked for me! I wasn't just blindly doing what they said!

    I've never been anywhere close to being a weight-weenie. I weigh 210ish, I tend to ride way out in deserted desert by myself and carry 10-15lbs of food/water/tools/parts, even for a much lighter/shorter ride. When I built up my Fatback, I was after maximum float and durability - and got 100mm double wall 36h rims. Heavy wheels. I'm still learning that they can roll over some of the roughest chunk around - whether from outer diameter, flex/float or plain momentum. I actually found out the other day that the best route over a rocky section was straight thru the worst looking part, rather than maneuver a torturous path of nicer looking stuff. Didn't even have to build up speed, just kept going at uphill arroyo cruising speed.

    When I first got the Fatback running, I was riding singletrack with my main riding buddy. His comment was "that thing sure doesn't slow you down any". He now has a Pugs complete, and the other day said "I never imagined I'd be riding this heavy of a bike thru this kind of terrain - and enjoying it!"
    This isn't a "you're doing it wrong" topic.

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