[Sandwich]

I'm not sure how they did the rounds, but it's reasonable to assume they would be randomized or at least rotated through. So, if he did one lap after another, I would hope they would at least swap bikes at the end of each lap, and therefore lap 2 would be faster on the 26 than lap 1 on the 29er by the logic that you present.

I don't think this is the indisputable proof that some of you need, but I think it's a pretty compelling argument that big wheels have some merit. I think it's particularly telling that the difference between 29 and 650b is not that large, while the difference between 650b and 26 is. They could have done a better job by not correcting the weight of the bike, for one thing. One of the drawbacks of big wheels is they weigh more. All things being equal, that's a benefit to small wheels. I agree that additional riders would be nice, and a subjective opinion to accompany hard data would be nice too. Perhaps blind the rider to the wheels they're riding, and see what happens. Somebody on emptybeer also suggested that one of the benefits of big wheels is the decreased need for tire volume...if you could get away with 2.1s on a 29er, 2.25 on a 650b, and 2.35s on a 26er, how will that impact the results?

Finally, I 100% agree that you'll get a significant increase in performance by going to a skills camp or spending a week in whistler than you would by just buying big wheels...but I still think free time is free time, and that's kind of cool.

 

[EVIL JN]

I have one issue though, the rider ability, does bigger wheels only mask bad ability in handling the downhill parts or would a dh pro benefit as much as a xc pro in dh sections? I do believe if a wheel size test should hold any merit the test should be performed under expected conditions of what is being tested will be used in, specifically a dh track with different skilled riders on a track they know extremly well. As far as i am concerned this test may only have established that as we learn a track we can ride it faster and not that a bigger wheel size give any real substantial advantage.

Cnsidering that the test used a ht i dubt much of the results, anyone remember the tire pressure test? Lower pressure in your tires were more efficient, the same principle they conclude would also hold with wheel sizes i think but what happens when we introduce suspension?

 

[Pslide]

If you want data of a different sort that shows 29ers are faster for XC, then go back to the # of expert XC racers running 29ers. These guys train 6 days a week and are fanatical about shaving 20 grams off their bike. You think they'd be running 29" wheels if they were slower?

And most people who've given 29ers a fair shot would probably agree. I do. Even Dirt magazine does.

Of course, this doesn't necessarily mean 29 will be faster for DH. The rolling and grip principles will carry over from XC to DH, but it's whether the trade-offs negate the advantages.

 

[Sandwich]

If you want data of a different sort that shows 29ers are faster for XC, then go back to the # of expert XC racers running 29ers. These guys train 6 days a week and are fanatical about shaving 20 grams off their bike. You think they'd be running 29" wheels if they were slower?

And most people who've given 29ers a fair shot would probably agree. I do. Even Dirt magazine does.

Of course, this doesn't necessarily mean 29 will be faster for DH. The rolling and grip principles will carry over from XC to DH, but it's whether the trade-offs negate the advantages.

100%, but I was under the impression that we're trying to talk math and not theory. MBUK has presenting a pretty reasonable study of wheel size in both downhill and uphill sections. I guess the real proof will be whether pros likes gwinnerd switch over and continue to dominate.

 

[MDJ]

In my completely scientific testing on downhill trails, using the same trail bikes in 26 and 29, the 29 is definitely faster. No question. The only type of terrain where a 26 was close was in very tight switchbacks that are hard pack with loose over. The 29 is faster in tight switchbacks with good dirt.

Comparing a 29 trailbike (135mm travel) against 160-170 AM bikes on trails better suited for the 160-170 bikes, the 29 was just as fast overall. The only slow sections are rock gardens where the lack of travel takes a toll.

Most importantly, the smile on my face was bigger with the 29. Er, except for the rock gardens. And you know what, I don't think I went home crying to my mama once about how flexy those big wheels where when slamming berms.

My 26 bikes still outnumber 29, but I sure am looking to get on a longer travel 650b (which is not 27.5). Beyond a Dj bike I can't see owning a 26 in a few years. I'm in no rush to get off a 26 DH bike but will not pass up the chance to spend time on a 650.

 

[PsyCro]

Someone test that same comparison with similar full-suspension bikes and then I'll care what it says. You also need a lot more than 1 rider for the stats to be significant.

^this^ .. and i'd even go as far as saying long travel full suspension bikes. Its the long travel rigs that concern us (especially here in the DooownHILL forum).

On short travel xc/trail machines the larger tire probably wins as well. I ride a full on DH bike and a Trek DS with 2.0 tires. The DS with large wheels is most definitely nicer/more comfortable/faster/etc to ride for mellow XC than previous 26er hardtails. But when i save up for a real AM rig, i'm gonna want it to be more similar to my DH bike in handling than a 29er hardtail.. IMO

In any case, much more testing is needed to REALLY come to a conclusion whether or not long travel rigs will benefit as far as the stopwatch is concerned. Personally i don't like that the magazine states that the test 'PROVES' anything.. THAT really sounds like a marketing scheme to me. The test only proves that larger wheels are better on hardtail XC bikes, which i'm sure most will agree that they are anyways.
rant over, for now! ...

 

[Pslide]

Some of Dirt's semi-objective testing can be found here. This is on full suspension bikes.

http://dirt.mpora.com/news/dirt-magazine-26v29-bonus-feature.html

There was an accompanying article in the mag.

 

[PsyCro]

Good clip in any case. Good points on both ends of the spectrum.
I must admit, i'm thinking about a Trek Remedy with 650b wheels for my next AM rig, but that Rumblefish is looking pretty capable as well.
Luckily for me, by the time i'm ready to buy a new rig, there will be much more info out there

edit. the most important point in the clip being time.. hmmm

 

[mtg]

I think using hardtails in the MBUK test was actually a good thing- it removed a significant variable that is suspension. That's one thing that I think a lot of comparisons miss: comparing more than one variable, and then contributing the results solely to wheel size.

For example, my current trail bike is a 33 lb 6" travel 26" wheeled bike with ~950 - 1100 gram "freeride" tires. I test rode one of the highly rated 29er "all mountain" bikes recently, and it climbed noticeably better than my trail bike. Could it be the wheel size? Maybe. But it was about a $10k bike that weighed ~26 lbs, and the suspension design and setup were different, the chainstay length is 0.9" longer, and the head tube angle is 1.5º steeper. I don't have enough data to say which was the most important factor, but my guess would be weight more than anything else. If my trail bike was 7 lbs lighter, that would have a profound impact on climbing.

So, the point is, as we are looking at different tests and our own comparisons, we have to be careful that we aren't measuring many variables at once and contributing all of the difference to one of them.

 

[OGRipper]

What is the coefficient of shimz yaw on a 26" wheel with a high volume tire vs. a 650B wheel with a low volume tire? Moar?

 

[Sandwich]

What is the coefficient of shimz yaw on a 26" wheel with a high volume tire vs. a 650B wheel with a low volume tire? Moar?

100% tactical root beer for freeriding.

 

[Tomasis]

for me "real" test is wait and see what WC riders do in DH if some wins runs on 650b, its enough for me

 

[DMdh]

for me "real" test is wait and see what WC riders do in DH if some wins runs on 650b, its enough for me

maybe if some top 30 rider start winning races because he rides on an 650b and the rest of the field ride 26" I could be convinced.

 

[no skid marks]

I have no doubt 650b will win(maybe not this year, I'm not sure what riders are on them yet, and I don't think the performance gain will out weigh skillz). I'm sure we will all end up owning 650b All MTN bikes at least. My question is, will it take the fun and zing out of it. Will it become less fun. Will it make it all feel more XCish. Will it make tracks change. I'm guessing we'll see less tight corners in tracks.

 

[Kanye West]

A quick tangent about load transfer: the neck of the woods that I was involved in with racecars used the terms of "elastic" and "geometric" load transfer to describe the difference between loads that came from the tires and either went into the springs & dampers, or directly through the chassis. In the mtb world, this would be equivalent to pivot height in the rear suspension. A BB-concentric pivot location has poor square edge performance because a significant portion of the tire load goes directly into the frame (high geometric load transfer) and feels harsh, or "gets hung up". A super high pivot, conversely, has higher elastic load transfer, and much less of the tire load goes directly into the frame without first going through the spring & damper.View attachment 112704

Could you go into further detail about how those two types of load transfers are parameterized? Any text or reference that you could provide?

 

[General Lee]

I have no doubt 650b will win(maybe not this year, I'm not sure what riders are on them yet, and I don't think the performance gain will out weigh skillz). I'm sure we will all end up owning 650b All MTN bikes at least. My question is, will it take the fun and zing out of it. Will it become less fun. Will it make it all feel more XCish. Will it make tracks change. I'm guessing we'll see less tight corners in tracks.

I don't think there's much cause for concern. Whatever the advantage it is sure to be small, maybe a few seconds on a couple minute long track at most. That's a big deal to anyone making a living by racing the clock, but is almost insignificant in any other context. DH track design is hardly an exact science anyway, there are plenty of sections that are less than optimal for long wheelbases or slack angles, or awkward slow sections with holes just the right size to swallow a wheel. That's sort of the nature of the whole thing, you can't make a bike or a devise a suspension setup that is optimally designed for every section of track, and tracks certainly are not designed around any specific aspect of bike design or wheel size. Though i wouldn't be surprised to see racers having the ability to switch between wheel sizes much like they do now with tires and adjustable bb eight and wheelbase.

As for taking the fun out of it or somehow watering down the experience, it is hard to imagine wheel diameter being that much of a panacea. Ask yourself: did wider bars, longer travel, better tires, dropper posts, and more aggressive angles hinder or enhance your experience? Is wheel size any different? Are they somehow going to gift skills to a less skilled rider? Doubtful. Who remember the late 90's when every sport racer who bought an M1 upgraded to the exert class and found out the hard way that they were still squids on track?

DH riders have always seemed to demand more and more out of their bikes and components. Better angles, more adjustable suspension, softer tires, better tread patters, lower bb's, adjustable headsets, stronger brakes, longer toptubes, wider bars, carbon frames.... an so on. Why all of a sudden such skepticism over a rather small increase in wheel size?

Is it because it trickled down from lycra wearing xc racers? Or are you afraid you might actually like it?

 

[no skid marks]

Or are you afraid you might actually like it?

I'm not afraid. I've been banging the drum since they started bringing 29er to market. Should've just gone straight to 650b I think it'll be cool. Will bring new standards n sh!t but.

 

[General Lee]

I'm not afraid. I've been banging the drum since they started bringing 29er to market. Should've just gone straight to 650b I think it'll be cool. Will bring new standards n sh!t but.

I know you're on board, I just quoted your post for the context. I'm certainly looking forward to trying 650 as well, it's one of the reasons I got a bike designed to accommodate both wheel sizes. It's just so odd that some of the same people who demand the tiniest bit of improvement on everything from mm changes to axle path and 10 grams on a shock spring, to skin suits and tiny sipes in tires treads are somehow instinctively resistant to a possible alteration in wheel size for no tangible reason other than "it's not 26." As if the 26" wheel was chosen for its own merits over a selection of other tested options rather than just being the wheel size that happened to be on some hippies cruiser bike in the 70's.

 

[EVIL JN]

I think the main argument is availability of good rims and tires both new 650b and the "old" 26. It would suck if we are forced to ride subpar parts because of forced obsolescence. Personally i dont care which size my wheels are as long as i can get a 823, minnion dhf's and wetscreams in 650b i am good.

 

[General Lee]

I think the main argument is availability of good rims and tires both new 650b and the "old" 26. It would suck if we are forced to ride subpar parts because of forced obsolescence. Personally i dont care which size my wheels are as long as i can get a 823, minnion dhf's and wetscreams in 650b i am good.

It's not a real argument though. It's a 'what if' that isn't based on any of the information that's been reported recently. You might not agree with some of the decisions product managers make, but they aren't stupid.

It's no big secret that tire/rim manufacturers are taking 650b seriously. From what I saw at the most recent industry show back in November every major player is planning to have a full line of 650b ready for the market (and some pretty sick 'enduro' specific stuff as well). Hence the all the talk about manufacturers 'killing' 26. Keep in mind that this is all talk in advance of MY 2014, not next month.

It's not like the 26" wheel will be gone overnight, or perhaps ever. Sh*t you can still get decent 24" stuff and that experiment has been dead almost a decade.

Relax, no one's 'forcing' you to ride anything.

 

[HardtailHack]

This all sucks because it means hipsters will be on "old school" 26'ers in the not too distant future, then I will have to change to Hula Hoop bike.

Just wondering, is a 29er wheel more likely to flat spot in DH as you often land directly on top of rocks, roots etc?

EDIT- From what Schwalbe say you can run a wide tyre at the same pressure as a narrower tyre and your rolling resistance is reduced as the wheel's contact patch is shorter make it effectively more round.
It works for 4WD's on sand so it should work for MTB, right?

 

[EVIL JN]

That's what i mean it is what if, i can still buy 26 823, minnions etc so my riding seem to be able to go on just as it has been. If 650b is what the market decides i will happily switch when that day comes.

I dubt big players like Mavic and Maxxis would let us down in offering good products in either segment for a long time to come, profits is profits and it will take a long time to replace the 26 market, so i think everyone will have time to swap parts.

As for product managers stupidity, no in most cases they are probably not stupid but often i find myself being quite annoyed with products which makes me look at their competitors products to find a better solution. Like the one mm of height on a Boxxer topcap bolt head, it would be so easy to make it a few mm higher and any problem of rounding it off would be gone but if you round it off they can also sell a complete MiCo unit as replacement. If that is good or bad for their companies business it is for them to decide.

All i can say is that I have taken more than one class in business management and i seriously question many bikecompanies strategies for their long run competetiveness, but that is just me though. I had a warranty issue with a 2011 Demo 8 inside a hour of recieving it, that issue was sorted fast as I expected but from there is was all downhill. A good bike to ride but was more a prototype than a production version for the masses, it had many small issues that just made it a headache to wrench on. Which meant less time to ride = not happy.

Sometimes the 50% moar stiffness in reality isnt worth the hassle for us weekend warriors that has to pay for, build and service our own bikes. I mean if i shave a few seconds of my lap times but end up spending more time with a wrench in my hand i think it is a bad trade off.

However what happens happens, I wont quit riding so i will adapt to whatever is offered and continue to smash berms and grinning like an idiot while riding 26, 650b or 29. I could do without a few headset and hub standards though but i guess that is another debate............

 

[no skid marks]

Will 36 hole hubs/rims make a comeback for 650b?

 

[General Lee]

Discuss

Maybe they'll finally have something new to talk about in the commentary booth besides flats vs clips.

 

[Sandwich]

looks like a short bike, how tall is the rider (i don't know who it is, sorry)?

 

[Polandspring88]

Steel is better than aluminum.

 

[iRider]

maybe if some top 30 rider start winning races because he rides on an 650b and the rest of the field ride 26" I could be convinced.

If that happens the beaten riders will petition with UCI because the big wheels 'make the sport look bad' and have them banned. It happened with skinsuits (which BTW are more of an improvement on the clock than bigger wheels).

 

[HardtailHack]

If that happens the beaten riders will petition with UCI because the big wheels 'make the sport look bad' and have them banned. It happened with skinsuits (which BTW are more of an improvement on the clock than bigger wheels).

No no, we are trying to work out the % gain of 29'ers so the people on 26" bikes can use electric assist to make up the difference so it is all fair.

 

[Sandwich]

Yeah! I mean it happened in XC, right?

ohwaitnope

 

[mtg]

Could you go into further detail about how those two types of load transfers are parameterized? Any text or reference that you could provide?

I'll dig up the text, but in the mean time, a couple examples that explain it are joeg's 100% horizontal wheelpath frame idea. Hucks to flat would suck, because the load transfer would be 100% geometric, and hence, no suspension movement from a perfectly vertical huck to flat. Conversely, a 100% vertical wheelpath would have 100% elastic weight transfer during a huck to flat as all of the load would go through the spring and damper.

 

[kidwoo]

A 10-20 second improvement on the downhill section alone, which averaged about 7.5 minutes and 2.2 miles, repeated over 4 rounds, while maintaining the same levels of power, by switching wheel size while keeping bike weight the same.

You've got your repeatability, you've got a predominantly controlled study, and you've got an improvement in 10s of seconds with the same rider on the same course....and you're debating that there's no value in the world of DH, where races are run by hundredths of seconds, because you've said so.

You people are worse than derp o'slurp when it comes to gun control. You're going to tell me that if somebody came up to you and said "I can give you 7 seconds improvement on your 1 mile downhill run, just by switching wheels" you'd say no?

If I raced hardtails, there's no question whatsoever that I'd race a 29" wheeled bike.



But racing hardtails is silly unless they have sweep bars and a beer holder, or unless you have a team to draft with.

That is the same non-information BS that makes me really dislike MTB media. It's not scientific at all but will get repeated as such. A sample of at least 100 deep would be real information. Same tire treads, same rims, and a whole shltload of different people to weed through who can pump transitions and who just rams into things and separate the line choosers from the line followers.

 

[Dogboy]

looks like a short bike, how tall is the rider (i don't know who it is, sorry)?

Floriane Pugin. I don't think she's very tall.

 

[kidwoo]

Is it because it trickled down from lycra wearing xc racers? Or are you afraid you might actually like it?

I was going to make a joke about anything ever productively originating in the xc race world that benefits dh equipment in the last 10 years..........because you and I both know it's almost always the other way around. Other than obvious material cross overs I can't really think of any. So yes, that's why

 

[slyfink]

Someone test that same comparison with similar full-suspension bikes and then I'll care what it says. You also need a lot more than 1 rider for the stats to be significant.

holy Christ, I can't believe how much discussion this new wheel size is generating so quickly... some people are even writing e-novels about it.

anyways, on to the back to back comparison request: http://www.nsmb.com/5422-stumpjumper-evo-head-to-head-test/

I didn't re-read the article but from I remember, there were some testers that were faster on the 29r, others were faster on the 26r, and some had more fun on the 26r and others had more fun on the 29r... not very conclusive. I'm just guessing the world won't end when I eventually have to upgrade to 27.5 when I can't find the 26" stuff I want/need.

 

[General Lee]

I was going to make a joke about anything ever productively originating in the xc race world that benefits dh equipment in the last 10 years..........because you and I both know it's almost always the other way around. Other than obvious material cross overs I can't really think of any. So yes, that's why

Even sticky rubber clipless shoes came from DH, and we don't even get off to run!

 

[sundaydoug]

Discuss

I wish someone would take a majestic B&W picture of me next to my bike while I look in another direction.

I'm also pretty sure those aren't 650b wheels on that bike if that's what you're getting at.

 

[slyfink]

I wish someone would take a majestic B&W picture of me next to my bike while I look in another direction.

I'm also pretty sure those aren't 650b wheels on that bike if that's what you're getting at.

Didn't the majority of Scott riders run 650b tires at the last world cup (or was it the world champs), and didn't most of those tires come off the rim (or was it that the rim exploded)? Anyways, my point is that...

wait, what's my point?

uuuh. I think that the DH teams are testing 650b for DH applications, and with the rims and tires they had at their disposal at that point in time, it wasn't quite there yet. But with the right rim and tire combo, maybe it won't be a problem? Logan Bingelli seems to have done pretty well at Rampage on his 650b bike...

 

[General Lee]

Didn't the majority of Scott riders run 650b tires at the last world cup (or was it the world champs), and didn't most of those tires come off the rim (or was it that the rim exploded)? Anyways, my point is that...

wait, what's my point?

uuuh. I think that the DH teams are testing 650b for DH applications, and with the rims and tires they had at their disposal at that point in time, it wasn't quite there yet. But with the right rim and tire combo, maybe it won't be a problem? Logan Bingelli seems to have done pretty well at Rampage on his 650b bike...

This is rubbish^^^

Claudio Calouri and their jr rider Noel Niederberger were the only two on 650b at worlds. Noel got 4th, Claudio ripped his tire off the rim on the crazy wallride that took out Neethling. He was not the only rider I saw fall victim to that thing over the weekend, certainly not something I'd blame on his tire/rim choice.


This thread is already full of nonsense, lets at least try to not to add more

 

[atrokz]

^ I believe one person did, and got a flat (prob due to poor rim/tire choice?). The majority didn't test them I don't think, and it would be hard to believe that Pugin, all 5 ft of her, is going to be trying them any time soon. You better believe every single works team WILL be testing them this winter, so we'll see the results for next years WC series I'd imagine.

Edit. There we go: 2 guys tried them.

 

[General Lee]

Edit. There we go: 2 guys tried them.

I believe Connor Fearon also used 650b, for 3rd place in Jrs