Tyre clearance

[Tom _M]

Current tyres are some 25mm Continentals. Any thoughts on whether I could get away with getting some 28mm’s on there? (Excuse the mud...)

[Your Dad]

Shimano list those brakes as being compatible with 28mm tyres, so it'll be down to frame clearance. What frame is it, and how tight is clearance around the chainstays?

[Tom _M]

Ah okay, that’s useful to know about the brakes. Frame is an Eastway Emitter. A good bit of room around chainstays:





There doesn’t seem to be any points closer than the calipers themselves, so may be okay possibly then...

[AndrewT1275]

Amateur.

You don't have clearance issues until you've had to cut off part of your frame and grind back your derailleur clamp.

[Tom _M]

AndrewT1275 said:

Amateur.

You don't have clearance issues until you've had to cut off part of your frame and grind back your derailleur clamp.

Blimey! Do you have to do temperature and barometric pressure calculations before you go for a ride in case the air expanding slightly in the tyre at the end of a ride causes it to rub?

[AndrewT1275]

On a more serious note, check the clearance between the wheel and the back of the seat tube. With a carbon frame you might have a bit of flex designed in the rear stays to smooth the ride which would cause the wheel to move up and towards the seat tube over bumps.

[AndrewT1275]

Tom _M said:

Blimey! Do you have to do temperature and barometric pressure calculations before you go for a ride in case the air expanding slightly in the tyre at the end of a ride causes it to rub?

No, it's self regulating. Any abraision removes material from the tyre or frame, bringing the gap back within tolerance.


Actually it's an older bike that I only use for tootling around and going to the pub on now. It was on 23mm tyres but it was very harsh so I've just put some 28s on it. They're brand new so still have the raggedy moulding lines which are making the gap look smaller than it really is. I reckon there's at least 2mm of useable gap there.

[Gribs]

Probably not if sticking with Continentals as they tend to come up big. My 25mm GP4000s II measure 28mm.

[Tom _M]

Well, I found an old 32mm Rubino Pro at the back of the shed and tried that, and as it just squeezed in, I think it should be alright.