Viewing 40 posts - 1 through 40 (of 42 total)
  • My theory for building the perfect UK trial bike
  • TrailriderJim
    Free Member

    It's been done lots of times no doubt, as I have done this myself, but take a 100-120mm XC/trail geometry frame (ie, a Trance) and stick a 140-150mm 32 fork on the front. This will relax the steep geometry and raise the BB just enough. This way, you have a light frame and fork with just enough travel at the back and as much as you need at the front.

    Add a good set of wheels (tubeless) and brakes and you have (in my opinion) a great all-round UK trail bike. Add all the other bits to taste.

    Just thought I'd share that with you. It's been on my mind since I woke up. 🙂

    grumm
    Free Member

    And invalidate the warranty and crack the headtube?

    GrahamA
    Free Member

    I don't think that you are the only person to think this – the Cotic Hemlock can be set up with 120mm rear wheel travel and 140-160 front.

    Although they have more travel the Orange Blood and Transition BottleRocket both have asymmetric travel.

    cp
    Full Member

    this has been done for years and years in one form or another…

    nbt
    Full Member

    It's been done lots of times no doubt, as I have done this myself, but take a 100-120mm XC/trail geometry frame (ie, a Trance) and stick a 140-150mm 32 fork on the front. This will relax the steep geometry and raise the BB just enough. This way, you have a light frame and fork with just enough travel at the back and as much as you need at the front.

    Or, get a Ragley Blue Pig (or MMBop) which is designed to work with a 140/150mm fork with a high BB and slack head angle. 😉

    bassspine
    Free Member

    perfect TRIAL bike no saddle, 50p bit for chain wheel, rigid fork and magura brakes. Ohhhh you mean TRAIL bike…. 😈

    ahwiles
    Free Member

    why do i want a high bottom bracket? – i'm a long legged 6'2", by the time i've got my saddle up to a decent height i'm about 12 feet off the ground.

    i like low bottom brackets as they bring me back down to a normal height.

    yes, i'm aware of pedal strikes, but i've just learned to time my pedal strokes.

    tinsy
    Free Member

    A bit like this you mean? My old bike, was lovely with a bit extra height up front. 100mm back and 120mm front.

    thisisnotaspoon
    Free Member

    high BB and slack head angles? That's Cannadian bikes, British bikes have always been low and steep by most's standards.

    TBH I prefer the old skool british geometry, the tight head angle (and resulting shorter weelbase) kep handling sharp at low speeds, and the low BB keeps the whole lot stable when the pace picks up.

    I_Ache
    Free Member

    Ive been thinking about this sort of thing recently and quite like the idea of a Stumpy/Fuel EX/Trance in a small size with some Pikes up front. A friend of mine has an old style trance with pikes and it is great he loves it its a bit heavy mind because he has a D321 on the front and an atomlab rim on the back as well as using a saint crank with an old mrp.

    The new breed of 4X fs bikes is what you are after if you want say 140/100 or a blood/bottlerocket if you want 160/140. I would love a blood personally.

    slowrider
    Free Member

    they just need to start making small frames with long top tubes so you can chuck it about but still climb well. low bb, steep seat angle, slack head angle, longer tt to allow short stem and a maxle rear end would be nice though…

    GaryLake
    Free Member

    There's some logic in this madness… but think 100mm rear, 120mm front, slack and built like a tank.

    Orange ST4…

    tinsy
    Free Member

    Nope dont build it like a tank, build it just strong enough, a tank would defeat the object I rekon.

    GaryLake
    Free Member

    tinsy, ok tank is the wrong word, but the ST4 can handle everything a 140mm bike can. It's just lower, lighter and faster.

    I_Ache
    Free Member

    ST4 with bolt through forks and tough wheels. Hmmmm that could work nicely wonder how much tyre clearance it has.

    mangoridebike
    Full Member

    I've done that, I've got an old Kona Dawg with 100mm travel at the back and a set of Pikes on the front. Set at 125mm it rides really nicely in singletrack, for steep rocky stuff I can wind them out to 140mm to give a slightly slacker head angle and bit more suspension.

    So far its been great and I think Konas are built tough enough to cope with a bit of extra travel on the front 🙂

    VanHalen
    Full Member

    i was told using cotic hemlock for jumpy fun was 'not suitable'

    a trance is cheaper to snap and replace. i wouldnt go 150 on a trance tho. 120/130 max.

    a prophet with a shorter stroke shock would also be good.

    the problem you get with smaller frames is seat post continuity. i like to slam my post most of the time but need a long post for commute/getting to the 'seat post slammed' parts. this rules out alot of frames.

    hicksville
    Free Member

    Had an older trance with pikes, great bike apparently Giant say okay upto 140mm see MTBR….daughters trance with pace 130mm currently. but see Blur 4x

    mangoridebike
    Full Member

    Thats why I like the Kona s continuous seat post. seat post all the way up for the long climbs, and all the way down for the descents. One of those suspension posts would be nice but I'm yet to be convinced about their longevity, or found one that is 27.2 and 400mm plus length.

    legend76
    Free Member

    i've put pikes on my scandal it looks great but it hasn't been ridden yet,glentress this weekend should find any weaknesses

    chakaping
    Free Member

    . i wouldnt go 150 on a trance tho. 120/130 max.

    Agreed, tried 140mm Revs on my Trance, was useless.

    Got a 120mm Reba maxle instead – perfect.

    thomthumb
    Free Member

    high bb's=unstable at most speeds imo.

    glenp
    Free Member

    The perfect trail bike. Well how about get together an international bike manufacturing company, with loads of highly experienced and qualified engineers and designers and pots and pots of money. Then spend decades refining ideas, testing designs, manufacturing and selling hundreds and thousands of bikes.

    So – the perfect bike then comes about by piggy-backing onto all of that multi-million pound investment and sticking the wrong fork on one of their bikes? You end up with a slow steering tank that then needs a shorter stem and a different riding style just to try and get some bite back into the steering that you have spent loads of money screwing up. All that to get "slacker" – what for? More stability going downhill. For why? Bikes are already great handling – due to millions of pounds and decades of development.

    tinsy
    Free Member

    My 04 Stumpjumper was a brilliant bike in stock form, but for me and the riding I did/do it was even better long forked, it didnt make it a barge , it didnt make the BB high, it just gave an XC bike a bit more you know, er gnar… 🙂

    1 inch only makes 1 deg difference, or there abouts to steering angle, it lifts the BB less than half extra fork length, and it doesnt rip off the head tube.

    Currently running a Scandal with 5 inch fork, a tad above the reccomended max and thats great too.

    On that note you be less likely to get away with a slacker angled already gnar bike then overfork it, but to a tight angled XC bike it can work.

    MrAgreeable
    Full Member

    Fitting a longer fork would slacken the head angle but also the seat angle, making it climb weirdly and doing odd things to the riding position. High BBs affect how well a bike corners dramatically. People go nuts for thin flat pedals that put you a few mm lower down, half an inch of BB height will make way more difference.

    I've ridden bikes that are designed around long forks and also bunged a longer than intended fork on a steep-angled frame. One felt fine, the other steered like a particularly slow-witted cow.

    james-o
    Free Member

    we did this to an anthem years ago, a shop project. it was fun but tbh the short travel rear / long front was better in theory than reality. great for committed hardtailers who don't ride fs often, but limited and unbalanced when compared to a more balancd, specific bike. 10-20mm more up front on a trail bike level of travel is never a bad thing though, much more than that i'm not so sure about, tricky to get the set-up right.

    chakaping
    Free Member

    glenp – I understand your point and I agree to an extent, 140mm forks on 100mm bikes don't always work.

    But surely the bike companies produce bikes that reflect what riders want to buy – and I'm sure they take inspiration from the modifications that keen riders make to their bikes anyway.

    Hence the gradual introduction of features from bigger bikes onto XC ones. Things like OS stems/bars, bolt-through forks, wider/riser bars, grippier (and slower) tyres.

    My money is on mismatched travel as the next mainstream trend anyway, since "going back to short travel" doesn't seem to be catching that well.

    rkk01
    Free Member

    this has been done for years and years in one form or another…

    Yep – Mine's called an RC305 😀

    If you really want a bouncy back end, they do that version too!

    tinsy
    Free Member

    I rekon though it would/could work for one bike I conceed it could be the downfall of another…

    Spankmonkey
    Free Member

    Like this? it was a 140mm frame with 160mm 36's

    Spankmonkey
    Free Member

    oh and btw the forks were talas in 140 it was fine in 160 it was a pig! 😆

    won't be doing that again!

    Olly
    Free Member

    have been tempted to get some of the new 140mm revs for my trance, currently on 130s.

    also been tempted to get a medium sized, old style trance and put some pikes on it, to compliment my XL new style trance gate.

    glenp
    Free Member

    Chapaking – of course bike design evolves. But it does so by a thoughtful and proper process. With designers and engineers and prototypes and lawyers and so on. Just imagine if a designer for Specialized said "Here's the new bike, we've done nothing to it except slap on the wrong fork. Handles a bit slow, but hey, it's slack! and that's a buzz-word in the magazines"

    The very fact that you can get a six inch trail bike off the shelf and no-one thinks that is weird is testament to the evolving ideas in bike design, esp towards tougher, bigger bikes.

    Anyway – the point is that ideal "UK" trail bikes already exist – they're called trail bikes and every manufacturer makes them.

    chakaping
    Free Member

    Olly, I wouldn't spend money on 140mm forks for the Trance without trying first if I were you. I did and it just didn't work for me. Was horrible. In my opinion 130mm is the limit, 120mm better.

    Glenp – I think we're in agreement actually, and most of the tinkering people have described on this thread is turning "XC" bikes into "trail" bikes, apart from the "slap a Pike on it" brigade of course.

    MrAgreeable
    Full Member

    Just imagine if a designer for Specialized said "Here's the new bike, we've done nothing to it except slap on the wrong fork. Handles a bit slow, but hey, it's slack! and that's a buzz-word in the magazines"

    I remember one manufacturer (I think it was GT) getting panned in a review for doing precisely that. But I expect the bike still sold to the "more travel is better" types… like me. 🙂

    richc
    Free Member

    i was told using cotic hemlock for jumpy fun was 'not suitable'

    Thats a shame. I quite liked the idea of getting one of them.

    cxi
    Free Member

    I've just stuck some U-Turn 20mm Rev's on my 2006 (shock-basket) Trance.

    Second ride on them was last weekend over Cut Gate. Even with the forks at 110m, didn't think it climbed as good as with the 100mm Rebas. I felt I had to get a lot more weight forward otherwise the front wheel kept popping-up (something I never remember on the Rebas). Need to move the seat forward and I've already been looking for a shorter stem (still on the OE 100mm).

    Thought the 20mm axle felt better, even though I do mince going downhill.

    I notice Rockshox.com lists the 2010 Rebas as being available in U-Turn (90 to 120mm) with a Maxle option. Now that sounds just the ticket…

    joolsburger
    Free Member

    Or you could go 100mm at the back and 120mm at the front, keep quick handling and have the right travel for 90% of UK trails IMHO

    richc
    Free Member

    I would like an adjustable 4/6" travel frame, 2.5 or less leverage ratio, DW link, ISCG tabs, maxle rear end which can take 150->160mm front forks and 2.5" tyres, which doesn't weight a ton.

    am I asking for much 😉

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