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[Closed] Minimum height axle to brace to fit a 27.5 in a 26 fork
I've an older RS revelation thats 150mm, 26". someones asked me if it will take a 27.5 but ive no idea. Anyone know what the minimum height from the axle to the underside of the brace would need to be to get one in.
Its on an urban use bike so i've got Schwalbe marathon almotion 26×2.15 on with it currently, which are quite deep. Not sure if theres a lesser option chunky tyre wise allows you to squeeze something in.
TBH im not sure, I've never used 27.5" so i wouldnt know one way or the other by eye
Depends on the tyres you want to run. Short answer is that you will need to run much smaller tyres so it's not going to work as an MTB.
A 27.5x2.2 trail king fits in a 26" fox 36 and the 2.2 trail king/rubber queen was a higher than average volume for a 2.2
2.25 and above probably unlikely but it would be a case of install and see if it clears teh arch, then depressurise fork and see if it clears the crown at full travel.
I think we'd best take this one as a no. Some things just arent meant to be.
I'll pass it along.
Easiest way to find out is to half the rim diameter for 650B (584/2 = 292mm), subtract it from the axle to arch height and whatever is left would be the size of tyre you can run without clearance. Obviously in the real world you need to build in a +/- tolerance but it should give you a rough idea.
FWIW on my old Revs I can fit a 2.3 DHF no bother and I'd even imagine 2.5 would be fine (it certainly was on the Marzocchis I used to run). 2.5 translates to a 2.24 in 650B and 2.3 to 2.0.
If you want I can send you an excel sheet that I made up to replace the sadly missed Bike Wheel Diameter Visualiser, it's handy as anything for figuring these things out on the fly.
Thanks for the offer SK, Im going to leave it all the same. I personally think it would be a bit tight, Axle to brace is 360mm. I'd guess the depth of a tyre would be about 65mm, give or take, which would really only leave 3mm to play with.
I might come up with or borrow a 27.5 wheel and ive a magic mary i could fit. Thing about bits of paper and measuring tapes its stil only a guess. Real world wheel and tyre i what i probably need to know for sure.
Thanks for the offer all the same.
And no hard feelings about the Ukraine thread. I can get a bit blowy at times.
I'm being good, and not went back in there 😆
On some forks the limit is the tyre hitting the crown on full travel. Well I got that warning on an old Marzochi fork
Ha, wouldn't take anything personally anyway, certainly nothing you've said, we're just shooting the breeze. FWIW I'll reply to your post in thread, you can read it at your leisure or not if you're not up to it.
You're probably right though, I wouldn't be trying to shoehorn a 650B into a 26" fork unless I was running road tyres.