Giant XTC 29er conversion to 27.5

Mountain Bike Mike

Well-Known Member
Has anyone attempted to convert a 29er xc to a 27.5? I am thinking of trying it out... I'm a small rider and I find the 29" wheels are big and clumsy. I do appreciate the "roll over" abilities but would like the bike to be a little more nimble.

I've been comparing the 29er & 27.5 geometry specs and there is very slight, subtle differences (a degree on the head tube / seat tube, and inch on the chain stay). I'm looking for some expert wisdom and if anyone is willing to lend me a set of 27.5 wheels to try it for a quick spin, that would be really kewl.

Cheers!
 

mstyer

Well-Known Member
An inch on the chainstay length (and fork) are kind of a big deal. Going to a smaller wheel will also drop your bottom bracket height .75" and make pedal strikes more likely.
 

michael.su

JORBA Board Member/Chapter Leader
JORBA.ORG
An inch on the chainstay length (and fork) are kind of a big deal. Going to a smaller wheel will also drop your bottom bracket height .75" and make pedal strikes more likely.

That's what I was thinking as well. Especially the chain stay length. That has a lot to do with being able to toss the bike around.
I didn't think about the lower bottom bracket... That could be annoying.
 

Mountain Bike Mike

Well-Known Member
Thanks for the feedback - You know, I didn't even think about bottom bracket height. That could be a slight issue with logs and stuff. I wonder how much of a difference that would be. Right now, I usually bunny hop everything but there is the occasional P.I.A log that I need to slowly get over while slightly scraping the big ring - in that case, I would be in big trouble.

I understand how the geometry of the head tube and rear chain stay would change things and I've always leaned toward a shorter rear section and steaper head tube angle because I like the "flickable" feel.

If anyone knows of a person or shop that would be willing to slap a set of 27.5 wheels on my bike for a quick spin around the parking lot, please let me know.

I am searching for a specific feel and I don't quite have it yet with my current setup. I really don't want to dump a ton of money and find out it wasn't what I was searching for...
 

Pearl

THIS CHANGES EVERYTHING
ya, you're doing it wrong. if you want to go 27.5, sell the bike complete and buy a new one, anything else just wont work.
 

gtluke

The Moped
that inch on the chainstays is what makes 29ers feel so truckish. combined with the inherent BB drop from having the centerline of the wheel higher than you want the centerline of the cranks.
You aren't going to change any of that with smaller wheels. You need a different frame.
 

Mountain Bike Mike

Well-Known Member
Thanks Gents, that is exactly the info I was hoping for. Now I need to find a demo soon to see if a 27.5 is more
Clickable and like Luke said less "truckish"
 
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