Viewing 40 posts - 1 through 40 (of 86 total)
  • 29er. for xc racing
  • backinireland
    Free Member

    Currently racing on one whippet built up fairly light.
    Seems everyone going 29er
    Wondering what’s about.
    My thought is that unless I spend a fortune I’ll end up with a heavier bike and be no better off

    cynic-al
    Free Member

    And you won be any faster

    backinireland
    Free Member

    On a 29er or on a heavier bike?

    large418
    Free Member

    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!

    cynic-al
    Free Member

    OP – on a 29er

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

    By how much? Your evidence?

    mtbmatt
    Free Member

    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.

    MBUK Wheel size test.

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

    backinireland
    Free Member

    Everyone with them just seems quicker than me!

    cynic-al
    Free Member

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

    “Emporer’s new clothes”

    njee20
    Free Member

    “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?

    cynic-al
    Free Member

    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).

    Bazz
    Full Member

    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 😉

    njee20
    Free Member

    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?

    cynic-al
    Free Member

    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.

    MSP
    Full Member

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

    large418
    Free Member

    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.

    darkcyan
    Free Member

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

    love my niner air nine!

    matthewspb
    Free Member

    @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 🙂

    njee20
    Free Member

    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![/quote]

    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.

    singlespeedstu
    Full Member

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

    rollindoughnut
    Free Member

    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.

    cynic-al
    Free Member

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

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

    singlespeedstu
    Full Member

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

    mtbmatt
    Free Member

    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.

    mtbmatt
    Free Member

    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.

    cynic-al
    Free Member

    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?

    🙄

    mtbmatt
    Free Member

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

    singlespeedstu
    Full Member

    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)

    The-Swedish-Chef
    Free Member

    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.

    cynic-al
    Free Member

    Stu, not interested in scientific proof then?

    Funny how you react so defensively

    singlespeedstu
    Full Member

    singlespeedstu
    Full Member

    Stu, not interested in scientific proof then?

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

    Funny how you react so defensively

    No, you’ve lost me now al.
    I’ll leave you to Bighit away all you want.

    Shaun20
    Free Member

    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.

    Kryton57
    Full Member

    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.

    cynic-al
    Free Member

    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?

    Kryton57
    Full Member

    Odd double post

    mtbmatt
    Free Member

    Its not very scientific though, is it?

    Please explain why you think this?

    large418
    Free Member

    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.

    Kryton57
    Full Member

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

    Edit: and now it’s back, bizarre.

    cynic-al
    Free Member

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

    No power data.

    DT78
    Free Member

    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

Viewing 40 posts - 1 through 40 (of 86 total)

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