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Discussion Starter · #1 ·
Anyone know how a shallow or wider rim effects the tire?

There seems to be a lot of 29ers riding 19-20mm wide road rims (myself included) and some riding wider 23-25mm rims. Anyone tried both and noticed a difference in how the bike handled, ride comfort etc.

I'm wondering if the tire handles differently ballooned on a narrow rim vs spread wider on a wider rim?

Anyone know if a narrower/wider rim effects the tires sidewall flex and it's ability to absorb bumps etc?

Premium Member
7,591 Posts
Good question!

Cloxxi - it might be worth adding this to the FAQ.

Lots of people are riding road rims, myself included. These go as narrow as 18mm. The widest rims out there for 29ers are in the 28mm range. I've ridden lots of different wheels at this point, here are my thoughts:

-Tire inflation width is not dramatically affected. From the smallest to the widest rim, the difference in inflated width is no more than 1/10", in my experience.
-Wider rims allow lower tire pressures. On road rims, pressures below 30 psi (again, in my experience) can cause the tire to feel really "squirmy" in turns and occasionally come off the rim.
-Wheel durability doesn't seem to be much of an issue, at least with reasonably well built 3x wheels like I use. I've heard of people using Ksyriums and such, that's probably a waste of money given that they aren't lighter than light conventional wheels, and the aero advantage is pretty useless for mountain biking.
-V-brakes can be a pain to line up with road rims, due to the thin brake track. Parallel push designs (ie Shimano XTR, XT) are easier to deal with.

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