If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

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redefined_cycles
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If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

Post by redefined_cycles »

Just pondering this Q as don't have as much experience messing about with 29er and 27.5ers. Usually I'd have good success topping forks up to 140mm where the bike was only designed for a lesser travel and (case by case) some handled the geometry change very well and remained perfect climbers.

Is the main thing I'm worrying about when trying to use 27.5 wheels on a 29er, the travel restrictions and pedal strike increasing... Or is there alot more science behind it and shouldn't be done.

Only asking cos I have these gorgeous Boost wheels (DT Swiss m1700) with 35mm rim width. Don't wanna be selling on and then realising they might have worked for the Santa Cruz Highball... Gut feeling is that I should just move em on as it'll probably be a daft move running 27.5 on that there frame/set.

Thanks in advance (and I'm totally rehabilitated, with the AK tolerance once again slowly entering my heart :smile: )...
Lazarus
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Re: If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

Post by Lazarus »

if you mean running 650 b + then there is not alot of size difference bettween them an 29 ers

i run My longitude with 650 b +in winter and 29 er wheels in summer/when less muddy
It rides fine with both

if you mean standard 650B I have no idea
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Bearbonesnorm
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Re: If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

Post by Bearbonesnorm »

As John says, if you're running B+ in place of a 2.3" or similar sized 29" wheel then the change will be minimal. If you're hoping to run 2.3" on the 27.5 rims, then I'd likely not bother.
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redefined_cycles
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Re: If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

Post by redefined_cycles »

Bearbonesnorm wrote: Mon Apr 19, 2021 10:12 am As John says, if you're running B+ in place of a 2.3" or similar sized 29" wheel then the change will be minimal. If you're hoping to run 2.3" on the 27.5 rims, then I'd likely not bother.
Ace. Thanks jon/stu... yes, I'll run em with the 3.0 or 2.8 whatever fits the gaps. Hopefully saved me some dosh :-bd
redefined_cycles
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Re: If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

Post by redefined_cycles »

Update: Oh dear, sounds like my plus wheels/tires won't fit :sad: (or at least I'll risk scrubbing the inside of the stays!) oh well...

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ScotRoutes
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Re: If a bike is designed as a 29er, is it just silly thinking to run 27.5 wheels?

Post by ScotRoutes »

Yeah, I don't think you'll fit Plus tyres in that frame. Even if you do, it still lowers the BB a bit (8-10mm). That's one of the reasons I had my Pact built with a relatively small BB Drop, so that running 650x3" would still give me pedal clearance.
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