Bicycle Doctor - faqs

Why do I keep getting punctures ?

Either you were very naughty in your former life, or the offending article is unfortunately still in the tyre. The most helpful thing to do is to list all the possible causes and then for you to rule them out one by one.

Sharp penetrative object(s) still in tyre e.g. glass
Inner tube is perishing
Look for signs of chafe marks on tube
Previous patch is leaking
Rim tape is off-centre, damaged or twisted
Valve is leaking; most common cause is a bent part of a presta valve
There is a rip/tear in the actual tyre
A spoke is protruding through the rim tape and piercing inner tube
The tyre pressure is too low
The tyre is too narrow (widthwise) for the width of the rim
The tyre tread is worn
In refitting the tyre, you have trapped the inner tube therefore causing a puncture

N.B. Try to avoid using tyre levers when refitting a tyre and try to avoid riding your bike in the gutter where the bulk of glass often ends up.