Tyre fitment

[KM2]

I’ve just been looking to see if a 50 mm width tyre would fit on a narrow internal rim width.
I found this which maybe of use to people.

Hooked rims

[Jdsk]

I find that image very difficult to read. What's the source, please?

Sheldon Brown's:
https://sheldonbrown.com/tyre-sizing.html

Schwalbe's:
https://www.schwalbe.com/files/schwalbe ... 020_EN.pdf

As noted by Sheldon Brown and by experts in this forum the recommendations from manufacturers tend to be conservative.

Jonathan

[Paulatic]

Looks like the pdf from Schwable https://www.schwalbetires.com/media/16/ ... 2-en-2.pdf

[KM2]

From Schwalbe, as I’m interested in Big Apples, 50mm.

[Brucey]

IIRC they say it is OK to use wide tyres on skinny rims; IME this might be OK for the tyre, but not for the rider necessarily; at lowish pressures certainly, sometimes all pressures, a wide tyre feels like it is about to come off around every corner, hence (I suspect) the discrepancy in advice.

[KM2]

I’ll give it a go, saves re rim for a time.

[kylecycler]

I run 50mm Schwalbe Big Apples on 19mm internal width rims and it's fine - the bike is a Carrera Subway and it came with 50mm Kenda tyres as standard.

I've also run 55mm Big Apples, though, and they're ok except you have to run them close to 40psi minimum, especially if the bike is fully loaded, or it tends to squirm at the rear - feels as if the tyre is 'folding under', 17mm internal rims with 50mm tyres would likely have the same issue but they should still work. I wouldn't go below 17mm, though, for 50mm tyres.

WTB recommend 24mm internal rims for their 48mm Horizon tyres as ideal, for what that's worth - that way you can run them at lower pressures for more cush, still with acceptable low rolling resistance, but without them wanting to 'fold under'; at least I think that's the idea,

There's also the potential problem of wide tyres blowing off rims that are narrower than ideal, but at the relatively low pressures you run them at, I'm not sure that's very likely.

[Jezrant]

MTBs ran, and some still do, 2.2” tyres on 17mm rims as wider rims weren’t common.

[KM2]

Thanks for your comments.