Quantcast

This is interesting: DH vs. 29" vs. 27,5" vs. 27,5"+

Mo(n)arch

Turbo Monkey
Dec 27, 2010
4,441
1,422
Italy/south Tyrol
Pretty interesting test they did up in Wales:


Still fastest on DH tracks: Downhill bikes.
Fastest trailbikes: 29"
27,5"+ is basically sh!t due to punctures and wobblyness.

I think 29" DH bikes will be seen in the future. For certain tracks like Ft. BIll for example it makes totally sense. Less fatigue = moar faster.
 
Last edited:

slimshady

¡Mira, una ardilla!
I'm not sold at all on the advantages of 27.5+. If you look at the stance they had on the 29ers or 650s compared to the that on the plus ones, you see most of them applying more weight to the front end on the balloon wheels, since as many of them said, the bouncing at high speeds threw them off line. And then is the issue with the paper casings they sport to keep them weights competitive, which makes them easier to fold in corners.

I wouldn't be surprised to see some more full DH 29ers in the near future though, given the new Super Boost standard would make for a stronger rear wheel.
 

Mo(n)arch

Turbo Monkey
Dec 27, 2010
4,441
1,422
Italy/south Tyrol
Seeing this I was actually surprised that we don't see more 29ers in enduro or even Megavalanche races nowadays. They all talked about how less abusive it is riding a 29er on long tracks so it's definitely an advantage if the tracks aren't too tight.
EWS Ireland was won on a 29er, right?
 

SylentK

Turbo Monkey
Feb 25, 2004
2,322
866
coloRADo
That was good stuff.

<enter usual comments/opinion on wheel size. Then be a dick about it.>

Love those soho/warner vids. Now to watch me some Dirt Shed Show!
 

Wuffles

Monkey
Feb 24, 2016
157
98
I loved this video. Showed that, unsurprisingly, DH bikes are faster on DH tracks, and it really comes down to the rider.

Also, plus may be fast in theory, but in practice you'll never find out because of a flat half way down the track.
 

Electric_City

Torture wrench
Apr 14, 2007
1,994
716
The Industry ™ had plenty of time to force that on us, but failed. They now invested in 27.5 enough to kill the 26. Why change now? If kickstand and myself (others too) can fell the flex of a 27.5 wheel that we didn't feel on a 26, just imagine how much more you'll have on 29. Forget your carbon ideology.

Ps. Fuck you Trek!
 

slimshady

¡Mira, una ardilla!
The Industry ™ had plenty of time to force that on us, but failed. They now invested in 27.5 enough to kill the 26. Why change now? If kickstand and myself (others too) can fell the flex of a 27.5 wheel that we didn't feel on a 26, just imagine how much more you'll have on 29. Forget your carbon ideology.

Ps. Fuck you Trek!
Hey, don't forget SRAM. They would pretty much jump aboard any new ship for the sake of "disrupting The Industry™".
 

Jm_

sled dog's bollocks
Jan 14, 2002
18,977
9,638
AK
They all talked about how less abusive it is riding a 29er on long tracks so it's definitely an advantage if the tracks aren't too tight.
EWS Ireland was won on a 29er, right?
And we still hear this BS about how 29ers can't do "tight". With virtually no gyroscopic force at slow speeds, this is just based on size perception (it's bigger and won't fit in the hole) and the impressions that people got riding wonky-azz first-gen 29ers with 18.5" chainstays and 73 angle head tubes. They do tight and switchbacks just fine, long radius fast stuff is good too, because you pick up a bit moar speed, but medium radius turns at speed are the 29s weak spot IME, riding and DH racing. In those turns you try to rail the line at the speed you want, but quickly find you'll slide out towards the outside of the turn, so you have to slow a bit, where smaller wheels will go faster. Maybe depends on the track, and I think we'll see some good ~6" 29ers that can be ridden at the park, just as there are a few now, but as full on DH bikes? No way. I loved riding the E29 downhill, very maneuverable most of the time, especially in tight stuff, but it doesn't turn (or jump for that matter) the same as the smaller wheels.
 
Last edited:

kidwoo

Artisanal Tweet Curator
And we still hear this BS about how 29ers can't do "tight". With virtually no gyroscopic force at slow speeds,
Who said it's because of gyroscopic effects?

It's the gigantic fucking wheel radius when leaned over that sucks. You have to turn and lean harder to get the same arc as you would a smaller wheeled bike with the same wheelbase. And of course all that leaning just pushes the tires closer to what they can handle.
 

Jm_

sled dog's bollocks
Jan 14, 2002
18,977
9,638
AK
Who said it's because of gyroscopic effects?

It's the gigantic fucking wheel radius when leaned over that sucks. You have to turn and lean harder to get the same arc as you would a smaller wheeled bike with the same wheelbase. And of course all that leaning just pushes the tires closer to what they can handle.
Noting the huge difference between my 1000+g minions and 800ish butchers, the rigidity-in-space gyroscopic force was absolutely real. Minions were good, but there were some tradeoffs, and this was one of them. I can remember what you are describing too, but IMO I was able to isolate these effects pretty well and you do take a hit on the medium turns at speed. One time I left the minions on for an epic ride....mother of god they beat the shit out of me. And yeah, if you want to DH, you still need serious rubber.
 

kidwoo

Artisanal Tweet Curator
I'm talking about this

And we still hear this BS about how 29ers can't do "tight".
They absolutely can't 'do some tight' as well.

I ride with a few really good (formerly) riders who for some reason have decided that taint ease is the number one priority in mountain bikes now and they ride road bikes in the woods. Former DHers.........get on a quick switchbacky trail and they're done. Like multiple bike lengths per turn done. It's like clockwork.

That said, stuff that isn't real turny, I think they're really good at not getting caught up in a bunch of shitty slow chunk. You just don't need any momentum to keep them rolling.
 

tabletop84

Monkey
Nov 12, 2011
891
15
Seeing this I was actually surprised that we don't see more 29ers in enduro or even Megavalanche races nowadays. They all talked about how less abusive it is riding a 29er on long tracks so it's definitely an advantage if the tracks aren't too tight.
EWS Ireland was won on a 29er, right?
Sounds like the biggest factor was familiarity with the trail.

Plus 27.5+ tires suck.
The setup of this marketing vid cannot be taken serioiusly. I mean when I go to a trail that I'm not really familiar with my time will improve with each run. So if I switch to a 29er after 4 laps I probabl will have faster times on that or vice versa. Plus like Monarch said if they really would be that faster you don't think that guys like Barel or Vouilloz wouldn't race 29ers?

The only way to settle this once and for all would be a setting were 20-30 pro riders would take their 27,5 and 29 rigs to a track their all familiar with. Then do as much laps as possible on each bike and then compare the average times.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,064
5,974
borcester rhymes
The Industry ™ had plenty of time to force that on us, but failed. They now invested in 27.5 enough to kill the 26. Why change now? If kickstand and myself (others too) can fell the flex of a 27.5 wheel that we didn't feel on a 26, just imagine how much more you'll have on 29. Forget your carbon ideology.

Ps. Fuck you Trek!
more money? you sold all the weekend warriors 650b, because it was better, now let's say 29 is better, and sell them another new bike. only with doubleboostyapplesauce at 165mm width.

29ers absolutely can do tight trails...just slower. A lot of the issue I have with them is the sheer size of the bike and wheel going from leaned in one direction to leaned in the other...it's a lot of motion to complete in a short amount of time. As far as Nico goes, isn't he like 4'9" (that's like 100mm for you euro types)? That's going to close the gap on any advantage bigger wheels have...he's just not tall enough to leverage them around.
 

livanh

Chimp
Jun 17, 2011
20
3
more money? you sold all the weekend warriors 650b, because it was better, now let's say 29 is better, and sell them another new bike. only with doubleboostyapplesauce at 165mm width.

29ers absolutely can do tight trails...just slower. A lot of the issue I have with them is the sheer size of the bike and wheel going from leaned in one direction to leaned in the other...it's a lot of motion to complete in a short amount of time. As far as Nico goes, isn't he like 4'9" (that's like 100mm for you euro types)? That's going to close the gap on any advantage bigger wheels have...he's just not tall enough to leverage them around.
Yeah and Tracy Moseley rides 29" because shes a giant.

Imo the problem with current 29" is the weight. A strong 29" tire + wheel weighs a fuckton compared to an equally strong smaller wheel. that just about cancels any advantage it has in rolling and grip, especially on shorter tracks.

the actual size really doesnt matter in about any corner - once youre adjusted to it.
 

Sandwich

Pig my fish!
Staff member
May 23, 2002
21,064
5,974
borcester rhymes
I'm not going to say that ladies enduro mtbing is at a much lower level than men's (because I don't pay attention to it) but if it's anything like ladies' DH mtbing, then it's at a much lower level than men's. Rachel atherton could ride a tricycle at this point and still beat Manon by 10 seconds.
 

livanh

Chimp
Jun 17, 2011
20
3
I'm not going to say that ladies enduro mtbing is at a much lower level than men's (because I don't pay attention to it) but if it's anything like ladies' DH mtbing, then it's at a much lower level than men's. Rachel atherton could ride a tricycle at this point and still beat Manon by 10 seconds.
well thats true. but i think that kinda supports my point. she is slow/light enough that wheel/tire strength is sufficient.
if turning with 29" would be a problem of wheel size and the relative size compared to the rider, she certainly would not use them.
 

Jm_

sled dog's bollocks
Jan 14, 2002
18,977
9,638
AK
Doesn't TMO say it pretty clear in the video? 29ers steamroll all the small trail chatter and in the long run that means ending the stages less tired than with smaller wheels.
They are the best for steamrolling over puppies and babies.
 

Cant Climb

Turbo Monkey
May 9, 2004
2,683
10
That track has hosted several muddy DH races i believe. It's going to have bomb holes on it that a normal trail might not have. The only time i feel 29r would be faster is flat-ish chunder, 27.5 gets hung up a little. Also i think 27.5 accelerates faster....when you have a short section of trail out of a corner.
 

4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,884
449
Love how it seemingly didn't even phase him and he just starts riding around again :rofl: