Viewing 40 posts - 41 through 80 (of 86 total)
  • 29er. for xc racing
  • mikewsmith
    Free Member

    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…

    molgrips
    Free Member

    What’s that Cwm Rhaeadr course like, btw?

    mt
    Free Member

    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. 🙂

    WildHunter2009
    Full Member

    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.

    njee20
    Free Member

    No power data.

    But there is power data. That’s the whole point! Sounds like it’s the same test TSC saw printed in Sweden.

    Rorschach
    Free Member

    [video]http://www.youtube.com/watch?v=5DjOL2we8ko[/video]

    mtbmatt
    Free Member

    cynic-al – Member
    No power data.

    Well as I have already said above there was power data (powertap) and HR, although I controlled the power and only monitored the HR. There was no real difference in HR, as you might expect.

    Each bike was the same weight and the tyre model was the same across all bikes (Hans Dampf) and 25psi across all tyres too – measured using a digital gauge.

    The uphill was 3.3km, mostly fireroad with the final 800m on singletrack switchback climb.
    The downhill was 3.7km, all singletrack and quite varied.

    I picked the order of bikes ridden out of a hat and each bike was ridden 4 times, over 2 days.
    I’m the first to admit it isn’t perfect, but its the best test I’ve seen to date still.

    Probably not good enough for you I’d suggest al. If it doesn’t agree with your way of thinking, then it can’t be right.

    MSP
    Full Member

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

    What a completely stupid statement :roll:. A person can only train so much to negate the disadvantages of equipment, unless you take loads of drugs as well just like LA and then claim its all about you.

    Why not train as hard as you can and take advantage of better equipment.

    large418
    Free Member

    Msp – that’s exactly the point the “stupid” statement was making. Glad you agree

    Kryton57
    Full Member

    To a point MSP. Albeit I’m not a fast or powerful rider there are many i know that’ll out perform me on a heavier lesser quality bike. Me running of and buying a light carbon 29er won’t change that although it may close a gap.

    Does the OP need to IMMEDIATELY justify a 29er? No he doesn’t. When he starts outperforming other riders on his 26ers and realising that actually his equipment is holding him back in certain situations, then perhaps he’d consider it. But it’s up to him, if his got the cash there’s nothing stopping him doing that now as long as he doesn’t get disappointed that his purchase is unlikely to launch him into the big leagues.

    chrispo
    Free Member

    On balance, I think my 29er is slower than my 26er but makes me faster. Make of that what you will 😉

    It’s all individual. Matt’s test gives the results for Matt. If I did the same test with my skills, the results might well be very different!

    And there are many other variables (geometry, tyres, weight, forks etc) that can have just as big an impact on speed as wheel size.

    But ultimately nobody’s making 26″ XC race bikes these days so the decision isn’t really ours any more.

    cynic-al
    Free Member

    My point is that folk saying “well my 29er feels faster” or “I went faster on it on my local loop” is barely anecdotal – so many other factors.

    So up to matt’s post below and the info available to me the MBUK test wasn’t very scientific and therefore not worth much IMO. If folk want to turn that into a cynic-al-flame-fest thqt’s up to you.

    mtbmatt – Member
    Well as I have already said above there was power data (powertap) and HR, although I controlled the power and only monitored the HR. There was no real difference in HR, as you might expect.

    Each bike was the same weight and the tyre model was the same across all bikes (Hans Dampf) and 25psi across all tyres too – measured using a digital gauge.

    The uphill was 3.3km, mostly fireroad with the final 800m on singletrack switchback climb.
    The downhill was 3.7km, all singletrack and quite varied.

    I picked the order of bikes ridden out of a hat and each bike was ridden 4 times, over 2 days.
    I’m the first to admit it isn’t perfect, but its the best test I’ve seen to date still.

    Probably not good enough for you I’d suggest al. If it doesn’t agree with your way of thinking, then it can’t be right

    I can’t see the power data, as I mentioned.

    That sounds pretty scientific, with the power data. I’d love to see it.

    molgrips
    Free Member

    I’d also like to see it repeated on different trails. To see if some wheel sizes are better on some types of trail. Also in the mud and dry.

    adsh
    Free Member

    I don’t have a 29er but what I notice when I am overtaken by them is that they deal with bumps, roots etc better. While I find the same route choppy they seem to float more – that’s not all down to technique or tyre choice.

    As a result on courses I ride my short travel FS they appear to be able to ride their 29er HT and get that HT pedalling efficiency.

    njee20
    Free Member

    So up to matt’s post below and the info available to me the MBUK test wasn’t very scientific and therefore not worth much IMO. If folk want to turn that into a cynic-al-flame-fest thqt’s up to you.

    You’re being a bit of a dick bigger hitter now, it turned into a “cynic-al-flame-fest” because you were sticking your fingers in your ears and shouting “lalalala I can’t hear you” when you were told there was empirical data, you chose to ignore that and carry on with your “it’s all just anecdotal” tack.

    Matt posted last page with:

    I think you will find that I used both HR and a power meter.

    And then the Swedish Chef posted the results, and you’ve posted 4 times since.

    Kryton57
    Full Member

    chrispo – Member

    But ultimately nobody’s making 26″ XC race bikes these days so the decision isn’t really ours any more.

    Ahem:

    http://www.trekbikes.com/uk/en/bikes/mountain/cross_country/elite_8_series/

    njee20
    Free Member

    An SLX equipped alu hardtail…? Not exactly a full on race bike!

    Interestingly though Trek did do a carbon 26″ hardtail last year, and they didn’t do any FS bikes. Spesh did the opposite – they went 29er on the hardtail first.

    I think it’s a valid point, there are few (I won’t say no) 26″ wheeled XC race bikes now.

    Kryton57
    Full Member

    The top of the range is XT with the exception of the cassette, race lite, and the material has nothing to do with the pendant content of this thread.

    Not exactly a race bike for who? For some it will be. FWIW my 26er probably weigh’s less than than that and I’ve raced it – does that mean I should consign it to trails duties and slap a carbon 29er in my shopping basket just for racing? And just becuase its en-vogue?

    Whereas in reality at my level it’d probably only make a huge difference to my bank balance and marital relationship, and therefore for the OP, the answer to his questions was what exactly?

    adsh
    Free Member

    One things for sure if you ride a 29er carbon race HT there’s no hiding in your equipment when you look at your results. Me I only ride a 26″ bike which no doubt accounts for my mid field placings!

    chrispo
    Free Member

    OK, *hardly* anyone is making 26″ race bikes now.

    When I finally kill my Whippet, am I really likely to choose a relatively old and low-tech second-hand 26″ frame over the latest all bells and whistles 29″ or 650b option?

    But for the time being, a second-hand 26″ racer makes very good sense VFM-wise!

    cynic-al
    Free Member

    njee20 – Member
    And then the Swedish Chef posted the results

    flame-fest was a bit facetious – only sstu was trolling. But no one confirmed SC’s results as the same test as matt’s (and they are imcomplete). In any event, SC states “227W +/2W” – does that mean an average of 227 over every climb? (can you control your power that precisely?) If not then the 0.9% variance matches the variance between the times (a total of 1.8%).

    singlespeedstu
    Full Member

    flame-fest was a bit facetious – only sstu was trolling

    Not trolling al.
    Just pointing out that i’d rather believe the results of Matt’s tests than you banging on about how unscientific they were.
    They seem to many people on here to be about as accurate as they need to be.
    If you think they’re not why not do some tests of your own and prove him wrong/right?

    mtbmatt
    Free Member

    can you control your power that precisely?

    Yes, because I did.
    I am sure I still have the power figures somewhere and I know for a fact that it wasn’t simply a case of the climbs at 225w being slower than those at 227w… if that is what you are getting at.

    If you read what The Swedish Chef wrote, he states that it was a re-print (news to me by the way).
    I doubt a swedish magazine would come over to Cwm Rhaeadr to replicate a test 😉

    What is it that you find so impossible to believe?

    The-Swedish-Chef
    Free Member

    Digs magazine out of the traditional rack by the toilet.

    Text by Matt Page, can we assume that is mtbmatt? I’d hazard a guess yes. You ride for Wiggle?

    One Felt six pro, one KHS six fifty 609, and one Felt Nine Team.

    All the same weight. Really?

    All with PowerTap rear wheels.

    It’s not hard to ride a known segment at pretty even pace/ power output, IMO.

    Again these results match my experience.

    mboy
    Free Member

    Probably not good enough for you I’d suggest al. If it doesn’t agree with your way of thinking, then it can’t be right.

    Late comer to the topic so I apologise, but absolutely LOVING the fact that we’ve got one of the UK’s most successful XC racers on here, having conducted proper research into this in the past, with (albeit a small quantity of) evidence and statistics to prove that like for like 29ers are faster… But that’s still not good enough?!?!

    Marginal gains are just that… They are marginal. The debate isn’t about how marginal they are, or how relevant they are to an individual, rather that there is lots of evidence (a lot anecdotal, but some cold hard stats) to suggest that 29ers are faster cross country than 26″ wheeled bikes like for like. To 99% of the public that’s neither here nor there perhaps, but if you’re trying to win a race, it can make all the difference.

    Look at road bikes for instance. Bradley Wiggins doesn’t turn up to a TT on a steel Audax bike. His bike is designed to make the most of the UCI rule book to make him as fast as possible. Running deep section aero wheels may only make him 0.5% faster over the length of a TT than running normal wheels, but that can be the difference between 1st and 10th place. Then you look at the skin suit, the aero helmet, the aero brakes etc. and all these incremental improvements may add up to a few % overall. Not to be sniffed at!

    I’d say looking at Matt’s data and times, 29ers seem to be anything up to 2% or more faster than the equivalent 26″ bike. I’m sorry but in the worlds of high performance competition, a 2% performance increase is an enormous difference! If you could put bigger wheels on an F1 car and make it 2% faster, you can guarantee that the entire of the rest of the F1 field would do the same by the next race.

    Of course, if you’re just riding down your local woods with mates, it matters not in the slightest, but that’s not the point being argued here…

    backinireland
    Free Member

    What about marathon events, someone states total dominance
    Why?
    Comfort factor?

    molgrips
    Free Member

    Good post mboy.

    I’d still like to know how tight and twisty a course has to be before the extra rotational mass of bigger wheels becomes a factor. Possibly within the range of XC courses actually, as a lot more energy goes into accelerating than it does rolling over bumps.

    The-Swedish-Chef
    Free Member

    Marathon events are even more suited to the advantages that 29ers have, they have loads of high speed rolling on fire/gravel roads, with reduced technical sections.

    DanW
    Free Member

    Absolutely LOVING the fact that we’ve got one of the UK’s most successful XC racers on here, having conducted proper research into this in the past, with (albeit a small quantity of) evidence and statistics to prove that like for like 29ers are faster… But that’s still not good enough?!?!

    Having seen Matt’s articles and posts in the past there doesn’t seem to be any doubting racing credentials or attention to detail in putting a race bike together (loved the pair of Rocky Mountains on Weightweenies a while ago!).

    However, as Matt as acknowledged himself it isn’t a perfect test. It is a good test but hard to draw any real conclusions besides the small amount of data providing some evidence for one user that the 29er appears to be the faster bike and certainly not any slower than the 26er or 650B on the one course tested. To say it is scientific though isn’t really too accurate though IMO. I don’t claim that a “scientific” test is easy though so I am certainly not intending to criticize and couldn’t do better myself!

    The small number of observations is an issue. Day to day variability usually requires repeat tests across 3-5 different days for most applications. Inter-subject variability? Again, 10 people would be the absolute bare minimum for anything like this to be published usually but some quick calculations based on the data might require a far higher number of testers are required. An interesting question is do 29ers yield advantages for all? Are 29ers advantages across all courses? You can keep the mean power output the same between repeat tests but is the total power delivered equally in the same magnitudes and at the same times between repeat tests throughout the duration of a lap? Are the lines taken each lap and the energy used descending (almost impossible to measure!) consistent? You’d imagine a skilled racer can control this pretty well but something like Principal Component Analysis could identify areas of highest variance between power and HR waveforms of multiple laps then use PC scores to determine if there is statistically significant differences in how the mean power (or HR) is applied across the lap. The tester was also not blind to the bike being used so may bias the results. A placebo 29er would be an interesting test too 😀 If the bikes were of equal weight overall then the rotational masses and distribution of weight would presumably be different between the bikes. How do you go about making the bikes “identical”??? You could go on and on!

    The test may not be scientific but the reality I think is that there are too many variables to control or account for to actually conduct a “proper” scientific test. Anyone who tried would leave themselves open to criticism one way or another and lets be honest it isn’t in the interest of manufacturers when the easiest solution is to just make all bike in one wheel size and force the change 😉 Experienced racers certainly don’t seem hindered by 29ers. All I know is Matt could ride a BMX and beat me on the pimpest whatever bike on any course 😆

    I don’t have a 29er but what I notice when I am overtaken by them is that they deal with bumps, roots etc better. While I find the same route choppy they seem to float more – that’s not all down to technique or tyre choice.

    Just to throw this in to the mix…. is a softail 26er faster than a 26, 650B or 29er hardtail? On a rougher, hilly course it would be interesting! Full sus vs hardtail more generally? Too many variables but at the end of the day I suck too much to ever need to worry so can be content with a rubbish 26 bike 😆

    njee20
    Free Member

    is a softail 26er faster than a 26, 650B or 29er hardtail

    Do you mean a soft tail, or do you mean a full suspension bike?

    Where do 29er FS fit into the equation? The Olympic champion rode one after all…

    DanW
    Free Member

    Do you mean a soft tail, or do you mean a full suspension bike?

    Either really I guess. I’m using a 26 flex pivot Scalpel which is closer to an old school soft tail in feel than a full sus which got me thinking. The frame is 1526g with shock which with a light set of wheels can’t be far off an equivalent top end 29er hardtail frame and equivalent light 29er set of wheels/ tyres/ etc in terms of overall weight. Less rotational mass but perhaps less rolling ability compared to the 29er hardtail? The Swedish Chef was on the same frame previously I believe and feels the 29er is still faster but it just throws up even more variables in selecting the fastest bike which I find very interesting.

    Where do 29er FS fit into the equation? The Olympic champion rode one after all…

    Even more variables and even more interesting. Do we know if it was actually used as a full sus or did it have the shock pumped up rediculouly hard to function pretty much like a 29er hardtail? From the few races I saw it seemed to be pumped up super hard which my cynical mind couldn’t help thinking might be a good advert for the full sus range but function pretty much like a 29er hardtail (albeit with a touch more frame weight). It is all interesting!

    ac282
    Full Member

    Specialized’s pros ride a variety of bikes. I don’t they’d force their top rider to use something he didn’t want to.

    DanW
    Free Member

    I agree. I don’t think anyone racing at that level would use anything that was detrimental to their performance. It did seem to be set up very firm though but it might have just been for those few races I watched.

    njee20
    Free Member

    can’t be far off an equivalent top end 29er hardtail frame

    You’re giving away 600 grams in the frame over a light 29er hardtail, yes the wheels will be slightly heavier (<100g), tyres likewise, but it’s still heavier.

    It did seem to be set up very firm though but it might have just been for those few races I watched.

    Guess it’ll still move on the big hits – a course like Hadleigh doesn’t really have many small hits. Had a look through my pics, but not got any decent ones where you can see Kulhavy’s shock whilst descending.

    ollie51
    Free Member

    Specialized’s pros ride a variety of bikes. I don’t they’d force their top rider to use something he didn’t want to.

    Specialized pros were told they’re only allowed to ride 29ers 2/3 years ago, whilst the 26ers were still on the market.

    Trek Factory Racing and their predecessors did the same, I mean look at Emily Batty’s setup on that 29er, looks a compromise to me.

    Giant riders also have to ride 27.5″ this year. It appears that Scott are the only big brand to actually offer their riders choice, well Schurter and Vogel at least.

    Nope, being pro means you ride what the marketing department want you to do. Specialized have been really good at this – new bike, bring in the best rider in the world to use, win world champs/olympics. Sauser and the Epic 26er (world champs), Cav + the venge(green jersey/worlds) and then Kulhavy with the Epic 29er(world champs/olympics).

    I guess you could call that last bit conjecture though!

    TheSanityAssassin
    Full Member

    Hey Al – just remind me what you rode the last time you did the IoM E2E. The one where you knocked 30+mins off your time from the year before and went from about 110th to around 58th? 😉

    To be fair though, I reckon that the kind of event like the IoM E2E, which is a mixture of road, gravel track and bridleway is where a 29er really excels over a 26er. From a personal point of view, I could live with the comparatively small ‘losses’ on the more technical sections because I reckon that the gains on the fast, open pedally sections will be pretty significant. It’s a question of playing the percentages.
    I suspect that the differences between 26er/29er will be much closer on a ‘proper’ technical XC race course that challenges handling ability and isn’t just purely a test of who can pedal the hardest.

    If you’ve ever entered a CX race on your 26″ mtb then you’ll know just how much harder it is to be competitive against the 700c opposition.

    adsh
    Free Member

    So do I want to make my pimp build 26 Ti HT and 96mm FS redundant/sell at massive loss for a 29er HT to pick up a max of 5 places midfield. Not worth it. If I threaten top 10 in supervets with my new training programme and increased age bracket (bet they’re just as competitive as vets :() I probably would.

    Can anyone ride a 29er HT for 12hour events?

    iomnigel
    Free Member

    Whilst not 12 hours, I rode a Niner Air 9 Carbon with Niner front fork at 10UTB and was fine. Also rode it at 24hr Relentless (along with an Orbea Occam) and was ditto fine.

    At 10UTB I rode over 100 miles (just) on her and whilst I was cream crackered I rode Enduro Enduro the next day…

    You will never be able to tell which is faster as even lap in lap out (on the Relentless) conditions changed and whilst the Niner always felt faster, the lap times were pretty consistent.

    Kryton57
    Full Member

    Adsh +1. You said it better than I could.

    But like I said if the op were awash with cash there’s nothing stopping him right? But he shouldnt expect a leap like the Sanity Assassin describes which is total BS – there’s no way his story is on every single factor like for like between the two years with the exception of the fact his mate rode a 29er on year two. Talk about a blatantly pointless post.

    njee20
    Free Member

    Can anyone ride a 29er HT for 12hour events?

    Seriously? Ant White uses one for solo 24s, as do plenty of riders. Ant does it particularly successfully.

Viewing 40 posts - 41 through 80 (of 86 total)

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