Lots of discussion currently abour mixing 29″&650b wheels.The Forks on my old stump jumper “old 130 mm pace” are crap.. I am only light so don’t need huge travel. Anybody tried short travel 650b forks on a Stumpjumper. I don’t need advice on changing bikes. but it would be a good time to thange away from QR wheels as well and I like tinkering. Just first hand experience advice please.

Stumpy’s have lots of incarnations but in general I’d not worry about switching fork to a 27.5.
You won’t add much to the stack by that alone but if you need to fit tapered to a straight steerer then your adding another 10-12 on top.

I need new forks as my 26″pace forks are hopeless. Seems an easy swap but quality 650b forks even second hand are far more expensive than Fox 32s which are available
For £100 sometimes on e Bay. Thought some 650b’s might give me a more modern ride though

You’ll need to check that they fit on full compression and don’t contact the frame, but otherwise shouldn’t be a problem. You’ll need to carry two tube sizes though for when the inevitable unsealable puncture happens

Nah, you can get a 26” tube to fit a 650b wheel.

I’ve no doubt they will fit but anybody done it and what does it ride like. bike is a 2007 fs Stumpjumper!

I’ve used a 26″ in a 27.5 to get me out of a bind, no issues. Not even when I removed it months later having forgotten I’d done it.

“I’ve no doubt they will fit but anybody done it and what does it ride like. bike is a 2007 fs Stumpjumper!”

I don’t think they will fit because you’ll be trying to put a tapered (1.5” to 1.125”) steerer into a 1.125” head tube. Quart into pint pot!

What headtube has the stump jumper got? If it’s 34mm ID for a standard straight steerer fork you are stuffed.

Edit: beaten to it by CGG. Missed the 2007 bit.
There was a link to some straight steerer forks on one of the french sites on here a bit back. Will see if I can find it

Fill your boots:
https://www.alltricks.com/C-40466-forks

I am aware of the mechanical pitfalls. Before I spend lots of dosh on an old but nice bike. I would have liked to hear that someone had done it and it rode well thanks

Why not just get a set of forks that fit? Some old Rev 426s or such?

Seems like a lot of expense and hassle just to fit the wrong fork. I still have nightmares of trying to track down forks for my Pitch.

Swapping to a fork designed for 27.5 and retaining a 26 wheel will raise your front end by maybe 10mm

I bet you don’t notice.

Crack on.

Putting a 27.5 wheel and fork on will be 20mm taller, you are gonna notice that.

Or buy one of those 26 rockshox from alltricks linked above.

Got a set of 27.5 Mattoc’s on my 26″ Saracen Ariel. They replaced a set of old marz, better performance and lighter, I think the axle to crown is pretty much the same.

I have an older 2011 Stumpjumper Carbon Expert, which is a bit like triggers broom. 🙂

However in its current configuration I am running a 150mm 650b fork up front (2019 Pike which has bolt through axle), with 26 inch wheels in it. I am also running a offset bushing on the shock to help bring the BB height back down.

All in all it rides well, it’s much more capable on the descents as the bike is slacker, and the new forks are much much stiffer than the old Talas that came on the bike. Its not quite so good on really steep climbs (mainly because I no longer have the travel adjust to drop the forks down to 110mm as I had previously, in addition to the already higher front end with the longer forks) but its not an issue for me.

Links to pictures:
https://photos.app.goo.gl/fbA5jHc98fid7mcT7

https://photos.app.goo.gl/Sy1zK91PvLobXx5X7

https://photos.app.goo.gl/8nAEsV3DeqVk6GFAA

Just run the 26″ wheels
There is nearly as much variation in stack height in a single “size” fork across manufacturers or running different tyres front and back.
You can reduce the travel by 10mm if needed but I doubt you’ll notice.

The challenge is finding the fork for your wheels/axle and headtube.
If you have to fit a tapered steerer to a straight tube then you add 10mm-12mm (CC/Hope) on top of the A/C.