Fastest wheel size?
- Thread starter 4130biker
- Start date
Good to see an actual study and in video summary rather than written papers or white paper reports (I read enough research papers as it is...).
This is of course all done on XC bikes which is likely to impact the results on the climbs, flats and downhills, and the researchers also note that even for XC bikes it is likely that different courses and riders may yield different results. It's a relevant study to continue with and possibly extend before doing anything more than hinting towards the directions that the current results point in (which is exactly what the researchers are doing, but perhaps the BR writer is taking as 'proof' a bit too much). I would personally suspect that the last few min are more relevant take-aways for downhill riding, but they do revert to interpretation and the (qualified) speculation this means (which is research-talk for 'we want to study this aspect further').
29er for overall speed vs effort on XC tracks that aren't too twisty in the downhill sections is no surprise to any rider, I expect, and that was the most visible result. The hint towards 26ers being quicker on the downhill but using up more energy to succeed with that shows what I personally have always felt on XC bikes: the geo on XC bikes need smaller wheels to comfortably go faster downhill, but that it feels like you're about to loose it the whole way. The more experienced you are with a wheel-size, the easier it is to push harder riding downhill. As none of the three riders had even ridden 27.5 XC bikes before, I'm not surprised it was slowest on the descents. It's freaking scary to ride XC bikes fast downhill if you're not familiar with them before! The researchers really should have lent the 27.5er to riders for a week or two to get used to before conducting the experiment. That was a major flaw in the study. (I have no opinion in terms of how that would have affected results - only that this likely impacted in ways they could have controlled better.)
So, if anyone shoots me the 100,000 GBP equipment they used, I'll offer my time for replicating the study for DH purposes and take it whatever direction may be interesting
This is of course all done on XC bikes which is likely to impact the results on the climbs, flats and downhills, and the researchers also note that even for XC bikes it is likely that different courses and riders may yield different results. It's a relevant study to continue with and possibly extend before doing anything more than hinting towards the directions that the current results point in (which is exactly what the researchers are doing, but perhaps the BR writer is taking as 'proof' a bit too much). I would personally suspect that the last few min are more relevant take-aways for downhill riding, but they do revert to interpretation and the (qualified) speculation this means (which is research-talk for 'we want to study this aspect further').
29er for overall speed vs effort on XC tracks that aren't too twisty in the downhill sections is no surprise to any rider, I expect, and that was the most visible result. The hint towards 26ers being quicker on the downhill but using up more energy to succeed with that shows what I personally have always felt on XC bikes: the geo on XC bikes need smaller wheels to comfortably go faster downhill, but that it feels like you're about to loose it the whole way. The more experienced you are with a wheel-size, the easier it is to push harder riding downhill. As none of the three riders had even ridden 27.5 XC bikes before, I'm not surprised it was slowest on the descents. It's freaking scary to ride XC bikes fast downhill if you're not familiar with them before! The researchers really should have lent the 27.5er to riders for a week or two to get used to before conducting the experiment. That was a major flaw in the study. (I have no opinion in terms of how that would have affected results - only that this likely impacted in ways they could have controlled better.)
So, if anyone shoots me the 100,000 GBP equipment they used, I'll offer my time for replicating the study for DH purposes and take it whatever direction may be interesting
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Well, that's also a way to go and tbh, I cannot find flaws in that reasoning!
Which in itself is very close to the gravel grinders and ultraCX races in (too) many cases. Incidentally, all who ride drop bars are on 28" wheels on those...
i can't remember which world cup it was last year, but riders were complaining about a "6 foot drop" on the xc course. when pictures finally surfaced on the internet it was a 4 foot roller. 
I like that they tried to control for many of the variables- it seems like this would be a tricky thing to study. I don't think any of the results are that surprising, but I won't lie that I was happy to see 26 was faster for the part that matters
This article also makes me wonder how much the optimization of travel and geometry for each size affects the performance of each.
I would love to see this replicated on a track with a steep gravel road climb, then a dh worthy descent on a longer travel bike like the Enduro where all three wheel sizes are available.
I thought people would be in more of an uproar about 27.5 not really being the best at anything, but I think might have forgot where I was posting
This article also makes me wonder how much the optimization of travel and geometry for each size affects the performance of each.
I would love to see this replicated on a track with a steep gravel road climb, then a dh worthy descent on a longer travel bike like the Enduro where all three wheel sizes are available.
I thought people would be in more of an uproar about 27.5 not really being the best at anything, but I think might have forgot where I was posting
mountain biking with the bane mask.
Was that the one where there was all sorts of riders panic braking and taking diggers off of the end and/or walking? That was some funny stuff.i can't remember which world cup it was last year, but riders were complaining about a "6 foot drop" on the xc course. when pictures finally surfaced on the internet it was a 4 foot roller.
The HA on their bikes and insanely poor performance on their forks to deal with anything but small bumps mean 4 foot rollers are terrifying. I totally agree it looks funny as hell though. It made you wonder why they didn't just bunny-hop down it instead...
yea i'm pretty sure it was.
Watching the last two WC races and worlds it seemed to me that at least on that level course are getting more challenging and it forced Absalon to ride a fully or he was losing time on the down hills.
That video was fun but it left me with more questions than answers.
That video was fun but it left me with more questions than answers.
Is there a video of these xc doods eating shit on said WC course?
This is the spot I was thinking of, but not the specific video. I think there's a compilation of just guys eating it/walking/skidding and all other sorts of shenanigans down this drop. Then the teenage girl jams through the rocks lol
http://bikemagic.com/video/video-cannock-national-xc-track-proves-hard-racers-carnage.html#LEbIlPL7zht1Ojpv.97
http://bikemagic.com/video/video-cannock-national-xc-track-proves-hard-racers-carnage.html#LEbIlPL7zht1Ojpv.97
Here we go again with this video.
That thing is about as scientific as the GOP's climate advisory panel.
That thing is about as scientific as the GOP's climate advisory panel.
The video framing it as a definite proof is a joke, yes. The study that they film isn't a joke though.
The study is pretty clear with what variables they control and don't control, as well as what they find under those circumstances. That is what you can expect in a scientific process. For that matter, I'm sure their paper on it will contain more details than a video for a bike magazine wants to have, but a single study is just a single study.
Just because it's not the ideal study that captures 'everything' (which is a myth to ever do, of course) doesn't make it less scientific. As all science, what you do is engage in a discussion and show what data and theory you build your argument around. Others may then do the same, either with the same variables or introduce other variables to discuss whatever differences and similarities that this may yield.
In this case, the researcher underlined that there was not a mathematical difference, but that the time difference on this course and for these three riders, with the three bikes tested, was clearly in favor of the 29er. That's pretty hard to call out as unscientific, especially without presenting a well-supported counter-argument. As I started out saying, the actual video framing of the study as some kind of definite proof is ridiculous.
The study is pretty clear with what variables they control and don't control, as well as what they find under those circumstances. That is what you can expect in a scientific process. For that matter, I'm sure their paper on it will contain more details than a video for a bike magazine wants to have, but a single study is just a single study.
Just because it's not the ideal study that captures 'everything' (which is a myth to ever do, of course) doesn't make it less scientific. As all science, what you do is engage in a discussion and show what data and theory you build your argument around. Others may then do the same, either with the same variables or introduce other variables to discuss whatever differences and similarities that this may yield.
In this case, the researcher underlined that there was not a mathematical difference, but that the time difference on this course and for these three riders, with the three bikes tested, was clearly in favor of the 29er. That's pretty hard to call out as unscientific, especially without presenting a well-supported counter-argument. As I started out saying, the actual video framing of the study as some kind of definite proof is ridiculous.
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I would love to know if the normalized to the wattage. There was a different "study" a couple of years ago in another bike mag where they showed that 29ers were faster. However, all riders put also a significantly higher effort into riding the 29er, so when you normalized the times against the wattage there was no advantage for the 29er.
I wait until I see the study to judge if it is scientific sound, but most of what I have seen so far doesn't have the sample size needed for propers statistics, e.g. not enough riders and not enough different courses/conditions.
This is excellent! I have just purchased a 29er a short while ago and after reading this article I now feel faster and much more smug compared to the rest of you common folk riding undersized wheels.
Regardless of the alleged scientific value of said video, I should hope the good people at strava start branding their own KOM oxygen masks so you can accumulate even moar statz
I interpreted the researcher stating (at the very beginning of part 2) that "if you look at it in scientific terms, there was no difference between the 26, 27.5 and 29 inch bike" as the normalized results. How else could he say that? He extends his explanation after a bit and to my ears make it clear that the normalization is what the statistical package is used for to reach the 'no difference' point.
A study can be scientifically sound without being able to generalize, and only the bike mag reporter tries to generalize beyond the three riders, three bikes, and specific course. You can tell this from the researcher and his repeated use of 'may be' and 'can be' as he's reflecting on the results. If he were to generalize and have sufficient data points for doing so, he would be saying 'is' instead. As I said in my first post (above my reply mtg's post), there is some speculation towards the end but that is just research talk for 'I want to continue this study'. Hopefully they can expand the study further, or that others expand it by replicating it, and perhaps also change some of the variables.
Bottom line is that the researcher also stresses that being comfortable on your bike is much more important in his view. The fact that both the reporter and the researcher laugh at the jokingly stated '...now we've got it all sorted out' in the end (9:25-9:35 mark) also says something about the generalizability in their minds.
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i'm only loggin in here to take credit for donating 3 bikes (one of which was a prototype) to the cause so we can definitely confirm that none of this nonsense actually fucking matters.
you're welcome monkeys
you're welcome monkeys
or, if you're a graphic designer, you conclude that the bike with no paint and decals is slowest
if you ever decide to do a scientific study about which tequila causes the rider to give the fewest fucks while riding, look me up.
Does he have to donate the tequila(one of which is a prototype) or the bikes?