johngwheeler

I'm running 28mm Schwalbe Pro Ones on my 2018 Giant TCR with the stock PR2 wheels, which have 17mm internal rim width.

I really like the Schwalbe tires (tubeless) which feel both fast and comfortable, and am considering upgrading the wheelset. I would probably go for something with a wider internal width, which makes me wonder whether the 28mm Schwalbes would still fit. Currently there is about 3 under the fork crown and a little more between the rear tire and the seat tube - about the minimum I am comfortable with.

I have read that wider rims can increase not only the inflated tire width, but also the height.

Does anyone have any idea (preferably first-hand experience) of how much a 28mm tire's height could increase when going from a 17mm to say 20mm internal rim width?

Thanks!

Dean V

I have them on Enve 4.5AR rims which are 25mm internal width.
I think rim bead heights may vary so the overall diameter might be a better measurement.
At 60psi mine measure 689mm.

shelbyfv

I can't give you numbers but can confirm it's a legitimate concern. A bike of mine could no longer fit 28s when I went to a wider (19 internal?) rim. Of course 25s now measure 28 on the wider rims, so I can't complain about the mfg claim of clearance for 28s.

shelbyfv

FWIW, it's still hard for me to grasp that a wider rim will make the tire taller. By golly it just seems wrong, though I've seen it with my own eyes! Nevertheless, facts are facts and there are plenty of charts and explanations online.