I accidentally won a speculative ebay bid on an old Stumpy Evo 29er frame last night.
Reading online the built bike was originally intended for a 140mm travel fork, my plan was to transplant most of the kit on my current HT including the 120mm Reba, but I'm thinking a 20mm under travel fork will steepen the HA and ruin the handling a bit too much and I'll just end up buying something longer anyway.
My other thought was would fitting an angleset address the handling in the short term. Anyone else done this? can a Stumpy frame take an angleset, and if so how will it behave? (lower BB, steeper Seat angle etc)...
This would only be a stop-gap so I can build it up this summer, if it's going to be a total dog, I'll ride the HT as is through the rest of summer and then wait till winter to strip the HT and build the stumpy up...
Steeper HA, and lower BB. Steeper HA would be a bummer as they were already quite steep on that, however the older Stumpies always felt quite 'high', (well, the two Iv'e ridden!) so I don't think dropping the BB would be such a bad thing. I guess very mucha suck it and see. Try it, what've you got to lose. Other than the price of a £30 headset, which you'd probably do well to keep on there anyways!
Can you fit a different airshaft to the Reba to increase travel?
Also I have a 26er stumpy evo which has integrated headset so I don't think I can use an angle set on it. Yours may be the same.
Smaller rear wheel?
#on-trend
I don’t think anyone makes an angleset to fit in most Specialized frames.
If you already have the bits, why not put it together and see how it rides. 20 mm shorter fork will basically steepen it by about 1 degree, which isn't going to make it unrideable.
Mrs’ Stumpy has offset shock bushes fitted, may be the route to take if you can’t use an angleset?
I don’t think anyone makes an angleset to fit in most Specialized frames.
I've not had the frame through yet but are they normally odd sized head tubes? Surely Works do something that would fit? what are the top/bottom ID's on Specialized frames normally?
If you already have the bits, why not put it together and see how it rides. 20 mm shorter fork will basically steepen it by about 1 degree, which isn’t going to make it unrideable.
I think it's actually coming with a normal headset, Stock HA was ~68* so run with the 120 fork it'll probably be ~69-70*ish. My current HT is ~67* with an angleset, of course once that's sagged that's probably more like 70* so it will probably feel quite similar to what I already know I guess, but I wouldn't mind getting the HA backed off and pushing the front wheel forward if possible, it's an unfashionably sensible HA as standard.
Can you fit a different airshaft to the Reba to increase travel?
120mm, 29er Reba RL (I think it might be an older OEM version too), so the A-C is on the long side for the chasis already and I don't think SRAM ever did a longer 29er version of the fork for that reason, if it's possible I'll look into it, but I doubt it somehow...
Mrs’ Stumpy has offset shock bushes fitted, may be the route to take if you can’t use an angleset?
Hmmm, now that Could be a good option, only question is will there be a risk of anything clashing on full compression with offset bushes?
Cheers all some food for thought...
All forks are pretty much the same length when bottomed out.
All forks are pretty much the same length when bottomed out.
20 mm shorter fork will basically steepen it by about 1 degree, which isn’t going to make it unrideable.
Less than that as a shorter fork will sag less than a longer fork.
Presumably you've got two potential issues. One is the overall geometry of the bike, the other is some sort of imbalance between front and rear travel. I guess if you found the latter bothersome, you could potentially use a spacer to reduce the travel of the shock or even fit a shorter overall shock if you have one lying around. But like a lot others, I reckon you should either build it up and ride it and see what you think. Or just save up for a longer fork.
Wasn't the EVO just the standard bike but with a 20mm longer fork anyway? If so it'll handle just like the the standard Stumpy of that age.
I think your weight will be too far forward and it'll be weird.
Offset bushings will be absolutely fine to do!
Travel imbalance is a non issue. I've run bikes* with more back than front before and you forget about it quick. You just hoik the front over stuff and let the back get on with it.
As long as the Geo didn't feel odd just go ride it. Experiment.
As above, offset bushes are cheap, sling a cheap 650b wheel on the back, have a play and see what feels good.
*Marins.
**Mozo pro 4.5 on a 6" rear FTW
***Also, in slightly more modern terms, a Patrol with a 130 Pike for a bit. It was actually a lot of fun.
I've had bikes with far more miss matched travel before, it's only 15mm different...
I googled a bit and yep looks like the angleset is a bit of a problem, headtube is integrated 42/52 might be able to get a bottom angled cup, but nobody does one for the top, so straight headset it is...
Looks like I can only use an offset Bush at one end as the shock uses an integral yoke on the other...
Oh and apparently on some of the early 650b versions of` the stumpy evo specialized put a 10mm spacer in the bottom of the head tube to jack the front end up...
Reckon I'll just run it with the Reba and an offset Bush for a bit and keep an eye out for a longer fork later in the year...
We have a medium Evo. If you are looking for a fork we took the 140 Pikes off after a few rides. Its still in the box at the back of the garage with the rest of the stuff I need to get round to selling.
Get our headset bearings from Blue Seal on ebay. Good quality and a reasonable price
Cheers but I'm too skint to buy a whole bike all at once right now... I might be shopping for some later in the year though.
Cheers.
