Viewing 14 posts - 1 through 14 (of 14 total)
  • XC v DH Top tube length
  • Bushwacked
    Free Member

    Chatted to a few people about this and had some good comments but wanted to open it up to the STW collective to see what everyones thoughts are…

    Background to this is I'm looking at getting a hardtail to rag downhills and have fun on – riding some steep technical hard hitting stuff and the like.

    Some people say a small bike (i.e. Small top tube) is more "Chuckable" but then I've seen others having DH HTs which have really long top tubes with a short stem.

    So for a bike more suited to DH runs should the bike ideally have a long or short top tube or similar to the one I have now (Soul in Medium with a 70mm stem).

    I understand that Cockpit size is important but how do I determine if compared to my current bike I can go smaller or larger?

    GavinB
    Full Member

    You could probably stay fairly close to where you are, with a shorter stem.

    For example, an Iron Horse Sunday (19") compared to a MkIII (19") has a 1" longer eff TT. You'll almost certainly run a Sunday with a 35-50mm stem, compared to say, 50-100mm for a MkIII, but you probably get the idea.

    JonEdwards
    Free Member

    Well I run a medium Soda with Rebas and a 70mm stem as my XC bike and have a small BFe with Lyrics and a 50mm one as my loony tunes effort. That seems to work fine, and it still climbs remarkably well for a bike that's technically "too small" It's certainly very easy to manhandle on really steep technical dh stuff – if I don't like the direction I'm going in, I can easily pick the bike up and stick it down somewhere different.

    I'm 5'10" by the way…

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    Bushwacked
    Free Member

    JonE – I've been thinking of Small BFe but this thing about Cockpit size has got me thinking… Also, maybe I should mention I'm 6ft…

    JonEdwards
    Free Member

    I think it kinda depends what you're used to. Robbie Rickman (Cotic sponsored 4x/DH loon) still rides a small and I think he's well over 6'. I think I'd struggle with anything smaller.

    If you've already got the med Soul frame, then you could always try sticking a 50mm stem on and see how it feels.

    Longer wheel bases will be more stable at speed, but one of the things I love about my Bfe is how nippy it is in real tight situations. You win some, you lose some…

    mboy
    Free Member

    You could probably stay fairly close to where you are, with a shorter stem.

    Sounds about right to me… All my DH bikes have been within 0.5" in length (though each of them a tiny bit shorter) than my XC bikes. I stick to 23-23.5" TT for an XC bike, and anywhere between 22.5-23" is where all my DH bikes have been (that's effective TT length BTW).

    As you've got a Medium Soul Barney, would suggest the Small BFe with a long seatpost for sure (and a 50mm stem). It's only 0.5" shorter in the TT, but its got loads more standover clearance. The Medium would be no different to your Soul, just a bit beefier.

    FWIW Robbie Rickman (Cotic sponsored rider) is 6ft3 and rides the small BFe, and he's a pretty bloody good rider! At last year's Megavalanche, he was just behind me on the grid for the qualifier. Start gun goes, he BLITZED past me (and just about everone else)… Needless to say, he did pretty well overall!

    ddmonkey
    Full Member

    I'd say shorten the stem and widen the bars, keep top tube length similar. Otherwise you will be banging your knees on the bars and hanging too far off the back which is not the best unless you are Brendon Fairclough. A slacker head angle with bigger forks should help with wheelbase / stability.

    Bushwacked
    Free Member

    Having ridden my mates DH bike I was shocked at how long it was and he's about the same size as me – what's going on there… ?

    kimbers
    Full Member

    my xc bike has the same tt as my dh bikes its just the stem thats shorter

    though my xc bike is a bit wee

    mboy
    Free Member

    Having ridden my mates DH bike I was shocked at how long it was and he's about the same size as me – what's going on there… ?

    Slack angles, long travel, long chainstays… All transpire to give you a very long, hence stable bike. And stability is the key measure for long travel DH bikes being ridden on World Cup level courses. An Orange 224, even the 15" which has a short 22"ish top tube, has an enormous wheelbase (probably 5" longer than most XC bikes).

    For what I think you want to use a BFe for, the ability to chuck it around will far outweigh overall length and stability. After all, if you wanted a mega stable DH beast, you'd be buying one with 8" of travel both ends right?

    Bushwacked
    Free Member

    Mboy – nail on head.

    I suppose a small BFe with something like 160 mm of fork the wheelbase will probably be similar to medium soul and if I'm hanging off the back a lot then again don't expect it to be much different…

    jedi
    Full Member

    cockpit size matters most so you have an area to move around in and move the bike around in. short bikes can make stiff backs 🙂

    mboy
    Free Member

    I suppose a small BFe with something like 160 mm of fork the wheelbase will probably be similar to medium soul and if I'm hanging off the back a lot then again don't expect it to be much different…

    I imagine if anything, it would be longer. With a 160mm fork you'll be raking the head angle out by over a degree compared to your Soul (130mm Revs iirc?), which will probably increase the wheelbase by more than half an inch which is all you'd be losing off the Top Tube.

    If you get a small BFe, you've got to let me have a go on it! So very nearly bought a small BFe frame numerous times now, and each time I nearly did, I bought another bike instead. I'm still very very tempted by one though, perhaps sometime in the future… Incidentally, we must go ride again soon, it has been a few months!

    Bushwacked
    Free Member

    Mboy – good memory – although the Revs were on the bike while my Pace RC40s were being serviced.

    Really tempted to get a BFe, especially now they come in that blue and the price has come down – only problem I've got to overcome is affording it!! 😉 May have to sell some stuff

Viewing 14 posts - 1 through 14 (of 14 total)

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