[Closed] 29er. for xc racing

And you won be any faster

On a 29er or on a heavier bike?

Like for like, on most XC courses a 29er will be quicker, but you will need to spend to get a 29er down to 26er weight. If you bought a Chinese carbon 29er frame and some light wheels and tyres you would probably spend nearly £1k, then transfer all the light bits off your whippet and you could have a 9-10kg bike for around £1k.

Of course, this could go upwards rapidly!

OP - on a 29er

large418 - Member
Like for like, on most XC courses a 29er will be quicker

By how much? Your evidence?

I've still not seen a test that covers the subject with more detail. It's not flawless, but its as close to a fair test as you will likely get in an outdoor environment. This was done with bikes at equal weights.

[url= http://magazine.bikeradar.com/2012/11/15/matt-pages-wheel-size-test-the-results/ ]MBUK Wheel size test[/url].

You would imagine that if 26" was faster then everyone would be riding them, but its the opposite.

Everyone with them just seems quicker than me!

mtbmatt - Member
You would imagine that if 26" was faster then everyone would be riding them, but its the opposite

"Emporer's new clothes"

"Emporer's new clothes"

Quite possibly, but they are pretty dominant in XC racing, Nino Schurter runs 650b because he likes an incredibly aggressive position and is only small.

You can use that argument about everything too if you really want. Suspension forks? Rim brakes? Gears?

njee20 - Member
You can use that argument about everything too if you really want. Suspension forks? Rim brakes? Gears?

No.

Those markets have LONG matured, tyre size has yet to do so - and punters aren't buying bikes on tyres size because they KNOW they are faster, only on feel or what why've bought into (actually and psychologically).

I feel faster on a 29er, however that is completely un-scientific so i could also say that i'm no slower but it feels like less effort 😉

punters aren't buying bikes on tyres size because they KNOW they are faster, only on feel or what why've bought into (actually and psychologically).

Whilst I was being facetious, and do agree to an extent, you can't really argue with the dominance in men's XC racing at the top level. If 26" wheels brought any advantages surely you'd expect to still see some riding them?

you can't really argue with the dominance in men's XC racing at the top level

Yes I blinkin' well can!

They are riding what they are paid to ride, which is what each manufacturer wants to sell - the differences in speed are marginal.

And if they are't marginal, and are measurable, tests would have been done and we'd all know otherwise.

They wouldn't sell many if they kept getting beaten by 26er wheeled bikes.

There's a lot of circumstantial evidence that supports 29ers being quicker - most of the top racers use them. Also some physics - if something has less rolling resistance and more grip, it should roll faster and corner better. Larger wheels generally have less rolling resistance over rough ground, and big tyre contact patches grip better - same philosophy is used in cars.

It may all be only a few % better, but at some levels that matters (maybe not to most of us though).

For what it's worth, I have a 26" Stumpjumper hardtail - 9kg, and also a 29er hardtail that I have just built up using most of the bits off the Stumpjumper - both bikes are the same weight. The 29er just feels quicker, partly because it is smoother through rough bits. I will probably use the 29er as my bike of choice as it just feels a nicer bike to ride.

It's taken me a long time to accept the marketing splurge, and I am not one to suffer continual upgrade syndrome (both my FS and HT 26ers are 11 years old and apart from maintenance and adding lightness I have not felt the need to replace), but having just treated myself to a new frame and wheels I have been surprised at the difference.

may not b quicker but are far more comfy,therefore easier to ride longer.

love my niner air nine!

@backinireland I've a 2012 stumpy comp carbon HT that I'm looking to sell in the not too distant if you're interested. Stock save for crests on hopes, ritchey carbon s'post and Easton bars. No doubt awesome for racing...
Good condition. Let me know if it might be of interest.
OpportunisticMatt 🙂

And if they are't marginal, and are measurable, tests would have been done and we'd all know otherwise.

Like Matt's you mean?

you can't really argue with the dominance in men's XC racing at the top level

Yes I blinkin' well can!

You can argue with the reasons, but you can't argue with the fact. It's a fact. They're dominant at top level men's XC racing.

al.
Post up your test results if you disagree with Matt's findings.
It'd be good to compare the two side by side.

OP I wouldn't spend too much time worrying about it. I race a 26" Scale, and whether it's geared or SS, rigid or susp fork at the time, I generally place around the same spot in the pecking order. I'd imagine on a 29'er it'd be the same.

Train your legs to get up the hills as fast as possible and train your skills to get down as fast as possible. I think the light 26'er is still a great tool for these jobs. The 29'ers seem to suit the seated, peddley, flatish sections so expect to maybe loose a few bike lengths here. Rest up a bit and don't fret and then smash them on the climbs again.

The MBUK test is a joke without HR and power data.

You say 29ers are dominant...in the entire field? Or results alone?

al.
Do your tests show HR and power data?
Post em up.
I'd like to compare the two different test.

They are riding what they are paid to ride, which is what each manufacturer wants to sell - the differences in speed are marginal.

While that may be true to a point, those same racers need to justify their sponsorship by doing well/winning races. Racers know that 29ers are faster, so they want them. It may only be a few %, but at the highest levels, that is a huge difference.

While they are mostly dominant in XC, they are totally dominant in Marathon events.

The MBUK test is a joke without HR and power data.

I think you will find that I used both HR and a power meter. The web version is only a short version of the test, the full version is in the published magazine.

Matt, it's not a go at you, I'd like to see the magazine test.

Stu, you are saying only someone who's done their own test can challenge a similar one?

🙄

It was published approximately 16 months ago.
Issue 284 I think.

al.
No i'm saying i'd tend to go with the results of Matt's published tests over your internet armchair expert views. 🙂

If the question was about STW bighittery I'd go with your results though. 8)

There was a Swedish magazine that re-printed a UK test with power data for the three different wheel sizes done at Cwm rhaeadr.

Summary:
3.3km climb done at 227watts, (+-2)
26 - 13:54
27.5 - 13:41
29 - 13:39

My own testing showed me a 29er was 90 seconds faster per hour than my 26er over the same XC course.

Stu, not interested in scientific proof then?

Funny how you react so defensively

Stu, not interested in scientific proof then?

Yes That's why I read Matt's test.

Funny how you react so defensively

For the majority of members on here it's not so much about how fast you get there but how much fun you have on the way.

Watching with interest, I've concluded that you're telling the op that he shouldn't waste any money buying a 29er. But could perhaps invest in training or improving his 26er

However, if He gets to National A or above, maybe he should, marginal gains and all that.

That's what your all saying, right?*

*crosses fingers 'cause that's what I've done.

singlespeedstu - Member
Stu, not interested in scientific proof then?
Yes That's why I read Matt's test

Its not very scientific though, is it?

Odd double post

Its not very scientific though, is it?

Please explain why you think this?

I think the conclusion (at least mine anyway) is that on some XC courses a 29er will be faster. How much faster and whether it's worth spending money on is down to the individual.

Or train harder and keep up with those who trained less.

The choice is yours.

Eh? My post which was a subdued somethingion between the rant has been removed. Pork Wah?

Edit: and now it's back, bizarre.

mtbmatt - Member
Its not very scientific though, is it?
Please explain why you think this?

No power data.

I am quicker on a slightly heavier 29er. My local loop personal prs on strava are evidence. If anything I'm less fit at the moment than 2 years ago when the previous ones had been set. Too many prs to be chance. I am however slightly slower descending for whatever reason.

If you got the cash do it, new stuff is nice, I picked up a scale, great bike

ANECDOTAL EVIDENCE ALERT....

I ended up doing a demo on a 100mm 29r FS bike over christmas on my local trails - ie ones I know like the back of my hand. Nothing too technical with a lot of pedaling required.

The 29r definatley felt faster, but wasn't actually that much (if any) than my other rides. It was easier up hills but that's in comparison to 160mm HT's and 150mm full sus bikes so not a fair comparison. I'd like ot go back to back with a good light 26" XC bike and really see what it's like but they are mostly in museums now...

What's that Cwm Rhaeadr course like, btw?

mikewsmith. My bike she'd is not a museum, it just looks like one. 20ibs Soda rides as well now as the day I built it. 🙂

Anecdotal evidence: Took a mate out awhile back, me on 26" Trek Fuel, him on 29" Giant. On trails i was much faster but on the tarmac climb back to the car he utterly destroyed me. Was a hardtail so that might have had a wee bit to do with it but i certainly got the impression on the 29er was faster.

I'm still not changing from 26" until the current bikes need replacing but i would consider a solaris i think.

No power data.

But there [i]is[/i] power data. That's the whole point! Sounds like it's the same test TSC saw printed in Sweden.