Whats the thinnest tyres i can fit on my 700c wheels?

[ibie1983]

Hello

The rim width of my 700c wheels is 25mm. I am therefore assuming these are hybrid wheels and require thicker tyres. Can anyone advise me whats the thinnest tyres I can fit onto my wheels?

Thank you
Ibie

[bobtravers]

Take a look at this site...

http://www.sheldonbrown.com/tire-sizing.html

A 44 to 57 size tire should fit

[DaveM]

(12-13-2013, 09:59 AM)bobtravers Wrote:  A 44 to 57 size tire should fit

Not one to dispute Sheldon, but I'd say that chart is a bit overly cautious. Putting a 28 or 32mm tire on a 25 rim is pretty normal. Fit is important the narrower you go. If you put a tire on and it seems loose on the rim/didn't take at least a bit of force to get on, you might be a little worried about a blowout. Some people go even narrower, but you really do want the bead of the tire fully engaged with the lip of the rim.

Note however, that for general riding, a narrower tire isn't necessarily faster. Overly narrow/hard tires will just transmit more road vibration up into the bike, wasting energy and tiring you out. Tread design and high quality, supple tire casings have a bigger impact on speed than width.

[nfmisso]

(12-13-2013, 08:29 AM)ibie1983 Wrote:  The rim width of my 700c wheels is 25mm.

Is that the inside width or the outside width?

Most wheels are sold by the outside width is pretty meaningless for the tire. A 25mm inside width is also very wide; most hybrid type rims are 18mm or 19mm inside width; which following Sheldon's conservative chart would be 25mm tire min. As Dave says, Sheldon is rather conservative in this chart; many 23-622 tires will work fine on 18mm (interior width) rims.

[ibie1983]

Hello guys

Thanks for the replies. @ nfmisso, the outside width of the rim is 25mm n the inside width is 19mm. So is it generally the case that if the outside width of the rim is 25mm, then a 25mm tyre n above should fit that rim? If i was to go one tyre size lower than 25mm, is there some chance it could fit that same 25mm rim or would that be pushing it?

Thanks again

[nfmisso]

You have to measure the inside width; no two models of rims have exactly the same side thickness. No generalizations are possible or reliable in this area.

[DaveM]

Unfortunately, I don't think there is a single, correct answer to this. It depends on rim shape, width, how tight the particular tires fit, how close they are to their listed size (this actually varies a lot), etc.

As a general rule, I wouldn't go narrower than the outside width of the rim. I've seen people do it, but it's a little sketchy. If the tire is sloping inward at the point it exits the rim, I don't think there's any way your getting good engagement between the bead of the tire and the lip on the rim. Matching rim and tire width is probably fine, but I don't think anyone can say that absolutely.

Again, I think the bigger question is what you're trying to achieve. If it's the narrow tire look, there's only so much you can do. If it's speed/performance, I'd worry more about find good quality, fast tires than trying to find the narrowest tire you can get away with. 23 vs. 25 is going to have little to no impact compared to what kind of tire it is.

[ibie1983]

Thanks for the replies i think i will try a 28mm tyre which should fit the 25mm rim ok.