Tyre size confusion

[Thistle]

I don't really understand all the numbers on these wheels, I've looked up several charts and am now more confused than ever.

Can anyone tell me what size tyres are appropriate for a wheel with this marking on it - I do understand that they must also fit the frame of the bike but if someone could give me some general advice I'd be grateful. The current tyres are old and very hard to read, I think they are 700c x 28. I was thinking I'd get 700c x 35 but is it possible to go wider if frame/mudguards allow?



in case the image didn't work, the direct link is here:

https://flic.kr/ps/3WuB4V

[Jdsk]

[Jdsk]

I suggest starting with Sheldon Brown's explanation:
https://sheldonbrown.com/tire-sizing.html

That page includes a table of compatibility between tyres and rims:
https://sheldonbrown.com/tire-sizing.html#width

and Schwalbe have another:
https://www.schwalbe.com/en/reifenmasse

Jonathan

[elPedro666]

Short answer: I'd be quite happy to run 35mm (and wider) tyres on those rims, frame/guard clearance permitting of course.

I'm a trendy consumer. Just look at my VOG-L09 using hovercraft full of eels.

[mjr]

Ignore 700C. It is an old French metric size equivalent to a 622 Bead Seat Diameter rim with something like 39mm tyres on it (622 + 2x 39 = 700). 700c x 35 or 25 or whatever is basically well-meaning gibberish.

The size to care about is ETRTO aka ISO standard measuring. 622x17 means the rim is 622 diameter and 17 wide, so the old rule of thumb (a tyre width that's 1⅘ths of the rim width) would put 27-622 tyres on it (which are rare), but as Sheldon's chart shows, you can vary it a bit.

[Thistle]

Thank you all, especially for the help in posting the photo!

It might be my menopausal brain but those charts still don't make a lot of sense to me. I'm assuming I can use 35 width but am wondering if 38 or 40 will also work, Schwalbe Marathon type, assuming they fit the mudguards, etc.

[elPedro666]

Thank you all, especially for the help in posting the photo!

It might be my menopausal brain but those charts still don't make a lot of sense to me. I'm assuming I can use 35 width but am wondering if 38 or 40 will also work, Schwalbe Marathon type, assuming they fit the mudguards, etc.

Have happily run 2"+ mountain bike tyres on 16mm id rims, so I'd suggest you'll be nowhere near the limit when you run out of clearance!

I'm a trendy consumer. Just look at my VOG-L09 using hovercraft full of eels.

[rotavator]

Thank you all, especially for the help in posting the photo!

It might be my menopausal brain but those charts still don't make a lot of sense to me. I'm assuming I can use 35 width but am wondering if 38 or 40 will also work, Schwalbe Marathon type, assuming they fit the mudguards, etc.

You can use a tyre upto 54 mm in width according to Schwalbe's table. I suspect that that is more than enough for you

[Thistle]

Thank you so much!!!

[NickJP]

The clearances on your frame will limit the maximum size of tyre you can use. That is, the clearance under the fork crown and seatstay bridge, and the clearance between the inside of the fork blades and chainstays at the point where the tyre passes through.

See, for example, https://www.renehersecycles.com/how-wid ... can-i-run/.

[Jules59]

The smallest clearance on my road bike (Boardman TC 2013) is between rear tyre and seat tube. I can just get away with 28mm tyres.