Capecodder

How wide a tire can be put on a 700x25 rim? I tried a wheel from my sons bike 700x35 and they fit and wondered how wide a tire will fit on the 25 rim. I want something wider with more thread for winter.

T-Mar

The rule of thumb is that tires 1.5 - 2.0 times the rim width will safely fit. For hooked bead rims, the upper limit can be increased to 2.25 times the rim width. Please note that in this case, rim width is the distance between the inside edges of the flange. The rims should be marked with a designation xx-yyy, where xx is the inside width betweent the flanges, in millimeters. An HB prefix designates a hooked bead rim.

Andrew F

Frame & fender clearance is probably more of an issue than what he rim will hold.

ColonelJLloyd 

+1

bobbycorno

IME, there's pretty much no limit to what you CAN run. I've run 35mm Paselas on Mavic Open Pro rims (19mm outside width, 13mm inside), and have heard of MTBers running 2+" tires on Open Pros. For best results, keep your tires no wider than ~2 x the INSIDE width of the rim. 28's are probably OK on something like Open Pros, but I've found the cornering behavior to get pretty spooky if I go wider than that, especially at the low pressures I like (50-60 psi in 35's).

SP
Bend, OR

ps - the latest trend seems to be to use the WIDEST rim you can: Zipp and Velocity are both making 23mm-wide rims for use with 23-25 mm tires. Supposed to make the tires more "tubular-like". I'm just glad there are some wide, light rims out there now.

YoKev

I ran 37's on Open Pros for many miles. It was really nice on bumpy pavement and gravel roads but handling was sacrificed a bit. I'm much happier on 25's now.

Mr IGH

35mm tire on a 25mm rim is not an issue, I'm running 56mm wide tires on a set of 25mm rims, it's very common for MTBs.

rjr2008

On a similar note, how narrow of a tire could one run on a 25 mm wide rim? I ask because I recently purchased a wheelset with Mavic A319 rims (25 mm wide). Mavic suggests range of 28 to like 47 or so. Might it be safe to run a 25? If so, would wire bead or folding make any difference?

Thanks,
Rich

Zaphod Beeblebrox 

once again, sheldon to the rescue. Bear in mind these are approxmations, you can go a little over or under the recommendation.

ColonelJLloyd 

My LBS owner rides a Trek 950 MTB with Schwalbe Fat Frank's (26x2.35) on what looks like a 22mm (outside width!) Mavic rim. Looks like it's about to pop right off the rim, but he has no issues with it. Obviously, true hooked rims go a LONG way.

Mr IGH

This table is a bike shop owner's dream, spec individual rims for narrow range of tire width, and claim it's a "Safety" issue. Imagine the potential revenue if was accurate and true (which it isn't).

old's'cool

Those are "narrow" ranges?!!

Zaphod Beeblebrox 

as stated its from https://www.sheldonbrown.com/tire_sizing.html