25mm tyres

[scotto]

looking for experience with regards to comparitive sizing for these tyres. Ive only used the michelin pro 25mm ones and on my new frame theres not really enough clearance. I know that in most tyres some are smaller or larger then their reported size. I'm looking for a smaller 25mm in other words !

[__PG__]

Use Continentals, they are much smaller.

I put Michelin Pro Optimas (they are a 25c tire) on my Hed rims for my new bike and the clearance to the seatpost and derailleur is very marginal. I was amazed by how much larger they were relative to the Pro 4 Endurance I had in a 23c. If I pick up any grit on the rear tire I will scrap the derailleur band for a few revolutions.

I did a test on the rear wheel and undid one spoke completely, I still have enough lateral clearance through the chainstays to ride home.

This weekend I'm going to do some detailed measurements of my
- Michelin 25c tire
- Michelin 23c tire
- Continental 25c tire
on a 23 mm and 19mm rim and post some numbers.

[munga]

don't forget to post numbers on your wheel too. wheel width surely plays a part in tyre diameter, yeah?

[biker jk]

Use Continentals, they are much smaller.

I put Michelin Pro Optimas (they are a 25c tire) on my Hed rims for my new bike and the clearance to the seatpost and derailleur is very marginal. I was amazed by how much larger they were relative to the Pro 4 Endurance I had in a 23c. If I pick up any grit on the rear tire I will scrap the derailleur band for a few revolutions.

I did a test on the rear wheel and undid one spoke completely, I still have enough lateral clearance through the chainstays to ride home.

This weekend I'm going to do some detailed measurements of my
- Michelin 25c tire
- Michelin 23c tire
- Continental 25c tire
on a 23 mm and 19mm rim and post some numbers.

Your HED Belgium rim is 23mm wide. That's why you have the clearance problem with 25mm tyres (which could be 26-27mm wide on this rim). On my 23mm wide rims a Vittoria Rubino Pro 3 23mm tyre stretches to be 25mm wide.

[__PG__]

Yeah I know.

A Michelin 23c on my HED rim is about the same dimensions as a Continental 25c on my old 19 mm rims.