Rear puncture at 30mph, wheel to blame? + is my wheel bust..

Bi50N

On route to Brighton on Saturday (just outside Smallfield) my rear tyre went, at speed, on a steep descent, with a bang - resulting in an instant flat. Rear wheel skittered all over the place, scary as hell, but managed to stay on. Think I ran on my rims for at least 100 yards...

Nothing wrong with the outer tyre. Found the hole on the inside surface, and not in a position where I feel it could have been pinched between outer tyre and rim. Couldn't find anything on the rim itself...

Any ideas how / why it might have gone?

Secondly - although not immediately noticeable afterwards, the bike soon developed a 'bump' at consistent intervals, as if I was riding over a bumpy surface. Have I distorted the wheel? It looks ok the the naked eye...

saladdays

Do you have rim brakes? If so, is the braking action smooth? If not then this could point to a damaged rim caused by the pothole that caused what sounds like a pinch puncture.

Also, have you checked the rim tape - spoke hole rubbing?

Bi50N

Disk brakes...

I ran my thumb round the rim tape before replacing the inner tube, felt completely smooth to me...

Long_Time_Lurker

Bi50N wrote:

Any ideas how / why it might have gone?

Secondly - although not immediately noticeable afterwards, the bike soon developed a 'bump' at consistent intervals, as if I was riding over a bumpy surface. Have I distorted the wheel? It looks ok the the naked eye...

Over-inflated tyre?
Pinch puntures can also occur when riding on poorly maintained (i.e.pot-holes) roads on rock-hard tyres.

Don't know about the rims though. I normally turn the bike over and spin the wheels. Should be able to spot it.
Check the spokes too. May have loosened a few. You might not notice if you aren't on it, but the extra weight of you sat on it may 'squash' the wheel. :?

Bi50N

Ta - it was set at 100psi, which I thought was about right...

I'll check the wheel again in the light tomorrow

desweller

Extremely unlikely to be an over-inflated tyre; they can take almost half the recommended maximum.

The original puncture sounds like either your rim tape doesn't cover up the spoke holes in the rim or you've pinched the tube when fitting it. This is more likely to happen if you use tyre levers to refit your tyre.

As for the bump, if the wheel is true then it's likely that the tyre is not properly seated; either because the bead has not been correctly located in the rim at some point or because the inner tube has a twist in it.

mudcow007

is your tyre fitted correctly?

make sure the bead (tough wire bit that hooks onto the rim) is seated correctly

if its not it can cause a slight lump which will feel like you have an egg in your tyre