Question: Does a wider rim mean you get a lower profile (height) to the tyre (tire)?

Equipment
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Situation: I have an older bike with limited space betwen the rear tyre and the seat tube. So at the moment I can only get a 23mm tyre to fit either with a 13, 15 or 17mm internal rim. If I try to fit a 25 on either of those rims it catches the seat tube or the band on front mech. So at the moment I can’t move to tubeless wheels or a 25mm rear tyre.

Question: If I fit a 25mm tubeless tyre to a (say) 21mm internal width rim (622x21), (eg a Hunt wide) will it have a lower profile than fitting the same tyre to a 15 or 17mm internal rim (622x17 or 622x15)? In other words I would get a smaller circumference with a wider rim for the same tyre.

If a wider rim would allow me to run a 25 rear I could get a set of much more modern wheels and still use them my lovely titatium road bike.

Any experience of this would be helpful, as I suspect people moving to wider rims (and tubeless) may have noticed a difference. Thanks

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Does the clearance change as you go to wider rims? I think this will give you the info needed to know the impact of a 21mm rim

Tires also gets wider with wider rims. So possible chainstay clearance may become an issue with a 21mm rim.

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yes that is correct, but you can only take it so far before the tire profile gets too far from the ideal shape.

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Narrow rims can make the tyre run wider, can’t they? That’s been my experience anyway. Enough to make a difference in this case is a bit of different though.

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Thanks @Leroy_People , I am cautious, as looking at teh conti rim size/tyre size tables it is out of spec., but the wheel manufacturer (Hunt) say they are OK with 25mm tyres so am not concerned.

Last night we tried a 622x19 with a 25mm tyre and there was a gap. Just enough. However it was a different tyre so it is possible that it might be due to the tyre design. There is not a lot of tolerance in this.

I am not worried about the width @Macy, though it does mean adjusting the brakes to fit.

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There might be a marginal difference, but something to think about … if it is so close now and if you win 2-3 mm by changing to a wider rim (doubtful that the difference will be as much as 3), that is still leaving a very small space. What can happen is you can hit a small piece of gravel on the asphalt, it sticks and then it lodges itself into that small space and slices up your tire as it continues to rotate until you’ve reacted to the racket.

Been there …

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The current gap between wheel and band on is 1mm (Its a bit more to the seat tube) and always has been since the bike was bought in 2003/4. That is with a 23mm tyre. I have occasionally picked up some gravel (sticky roads etc.) bit it has never been a problem. It just flies out.

I have looked at having a braze on fitted, but the frame is titanium and the company say it is not wise to try and weld onto existing material. They would not warranty it.

This is more about getting some newer wheels for it, to use across several bikes, but I did not want to get some and find they did not fit my favourite summer road bike.

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As they say, YMMV.

Sounds like a tight fit the way it is. I’d probably go for new wheels, but still put 23mm on them for that bike.

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@dlridings Thanks. Interestingly last night we also tried a wider wheel with a 23 tyre on it and it caught the rear mech. Unfortunately the wheel did not have an obvious size on it but we think it was a 17 or 18.

Must say I am heading for stick with what I have… it seems a whole lot easier and simpler.

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