Switching from 27.5+ to 29

I’m sure this has been asked before, but can’t find it (and that never stopped anyone anyway!)

I have a Vitus hard tail, which I want to get some better wheels for (spec here https://archivevitusbikes.com/products/sentier-vrs-2018/).

Other than taking the kids out around the woods, I haven’t ridden the thing properly in years – mostly grav/road now. But it would be nice to get some 29 xc wheels and tyres on it.

It came with 27.5+, 2.6 tyres.

Is it feasible to switch to a 29 wheelset from 27.5+? Wonder if it’ll fit in the fork, or screw up geometry, or other things I haven’t considered..

My “bikepacking” hardtail normally wears B+ wheels and tyres {45mm rims and 3″ tyres) but quite happily runs on 29×2.2 when my route suits those better.

A few years back, there were a lo of bikes designed around both 27.5+ wheels and 29er wheels, but not all, sometimes the chainstays are shaped to fit the 27.5 but not the 29, can restrict tyre choice, etc – 29er wheels are a bigger radius

Same with the fork, a lot of bikes came with 29er forks, and the 27.5+ wheels fitted, but your bike might have 27.5 forks designed to fit wide tyres

Geometry wise, it will make your BB a bit higher, I didn’t think I’d bee super sensitive to that, but I found it really odd when I changed to 29, felt really high, despite only a half inch or so difference

I’d definitely try to borrow some 29er wheels to see how it looks before buying anything, reading the spec above, it looks liek your bike might not have had 29ers in mind, so 29er tyre choice might be limited

IIRC the difference in radius between my 27.5×3.0 and 28×2.2 tyres is around 9mm. You could check your frame and forks for that clearance.

I’ve got a ragley marley which is designed around 27.5 2.6 tyres.

29×2.25 fits…. just. But it rubs on the frame a little in some situations.

It also feels a bit weird with the super short 27.5 stays.

My old whyte 905 wouldn’t fit 29’rs

The radius of a 29″ wheel is about 20 mm bigger than a 27.5″, so that’s about .75 inches. Best to try to borrow a 29″ wheel and see how much clearance you have, otherwise measure how much clearance you have with your current tyres and map out the clearance if you move everything out by 20 mm.

Why change wheel diameter? 27×2.6 tyres are still available? I still have 2.8s on my rigid single speed!

It will still ride over stuff and the fatter tyre will be more forgiving than a 29er with a skinny tyre.

Thanks guys, I did suspect it might not work.

@VanHalen there’s not tons of choice for 27.5 now, still a few, but most stock of wheels and tyres seem to be 29. Hunt have only one set of alloy 27.5 (which I’ll probably get), but loads of 29.