I'm toying with the idea of trying a 29 wheel on the front of my 650b orbea rallon. I love this bike, it's fast and composed allready, but I love the big wheels on my xc bike. (Whyte t129)
I was wondering if anyone on here has tried anything similar? I can see it being the best of both worlds.
The orbea currently runs a 160mm fork with a very low bb. My issue is whether to get a 160 or 150 mm air shaft to try in my 29er pike.
It will only really be used for 'enduro' type riding where I'm not bothered about speed on the ups or easy flat sections.
What do you reckon?
Has anyone else done anything similar?
The 29" wheel will add about 40mm of front-end height if you keep the same travel, so if you want to keep the geometry the same you'll need to drop to a 120mm fork. If the reach is long enough, the seat angle steep enough and the BB low enough then you could go with a 140mm Pike and that'll slacken the angles by about a degree and raise the BB by about 6mm.
Hmm. Interesting. Would I lose the benefits of the big wheel by losing travel on the front do you think? I'm wondering if shoving an offset bushing in would help keep the bb low.
The bike has adjustable geometry anyway, yeah? Which setting do you usually have it in?
29er front/650b rear can work really nicely, but I think it's easier to get something workable by putting a 650b rear in a 29er frame.
That's what I did a while ago and it was awesome...
http://unduro.co.uk/mtb/behold-the-frankenthumper-aka-project-279/
You could put something like a Flatforce stem on which would help lower the now higher front end:
http://www.syntace.com/index.cfm?pid=3&pk=2629
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It does have adjustable geometry. I allways run it in the low and slack setting. I'm going to look at the axle to crown measurements on my xfusion slants compared to pikes. I'm thinking 150mm may be a good setting. I'm just wondering if I'll really notice a difference.
it'll add a bit less than 20mm of height to the front end, assuming you have like for like tyres on the two wheels.... Although, my Ardent 27.5 looks like it has more volume than the same tyre does on the 29" wheel
Do you have to commit to the Pike air shaft length before you can try it out?
150mm seems like a decent compromise to me and offset bushings would certainly help - I think you will notice the difference with the big wheel. Make sure you let us know how it goes.
it'll add a bit less than 20mm of height to the front end, assuming you have like for like tyres on the two wheels.... Although, my Ardent 27.5 looks like it has more volume than the same tyre does on the 29" wheel
The bigger wheel adds 20mm and the fork adds another 20mm, unless you're going to try to fit a 29 wheel in a 27.5 fork...
I assumed he was already running a 29er fork on it....
I kinda agree with [b]chakaping[/b] on the 27.5 in a 29er frame idea. I don't think you'd lose anything by running a 140mm 29 wheel and fork, I think that that copes with bumps etc much better than a 160mm 27 wheel and fork. I've tried both up front and think the 29er is better but that's only personal opinion. I've not tried mis-matching the wheelsizes though.
Bungalistic. Tgat is what j wanted to hear! I have a 140mm airshaft for my pikes at home, so I'll try that 1st.