Bloody punctures

[Darren Jeffrey]

I've had 2 punctures in the past 2 rides both on the back wheel. I've checked the tyre for debris and the rim tape is in tact also. It's the same tyre and tube I have on the front and had no bother with that.

I can't see on the tube what this problem has been so was thinking possibly a valve issue?? The tubes are the btwin cheap ones but never had any problems with them in the past year.

Just been unlucky??

 

[Tim Hall]

If it's a puncture, something will have pierced the inner tube. A bit of flint, a thorn, sliver of glass etc. These will leave a hole in the tube (duh) from which the air will escape. If there's no hole for the air to escape from, then yes, it could be a leaky valve.

 

[theMec]

Obvious one, but have you tried inflating the tube then submerging it in water, slowing rotating it ? Might help you find the offending hole. If you don't see any bubbles it's probably the valve.

 

[Ben M]

How many miles have you done on the tyre? It could be worn and not as thick (and therefore puncture resistant) as it used to be.

 

[Maz]

Have you tried pumping up the inner tube to find out where the leak is coming from? Can you hear a hissing noise or 'feel' the air coming out?

 

[Darren Jeffrey]

Ok found the issue. Tyres where brand new

There was the tiniest piece of glass lodged in the tyre. Small enough that I can't even photograph it for this thread lol. Both inners punctured at the same area.

Lesson learnt. Thanks for the replies

 

[andytheflyer]

Ok found the issue. Tyres where brand new

There was the tiniest piece of glass lodged in the tyre. Small enough that I can't even photograph it for this thread lol. Both inners punctured at the same area.

Lesson learnt. Thanks for the replies

I always run my fingers around the inside of the tyre to look for a thorn or something else sharp that's penetrated the casing, before refitting a tube - but take it slowly - otherwise you end up with punctured fingers too......Ask me how I know.

 

[Davidc]

Hint - when you take the tube out try to identify where the air is escaping and match up the position on the tyre - speeds up finding the problem.

Be careful with fingers - A year or so back I had a puncture caused by a discarded syringe needle which was still in the tyre!

 

[slowmotion]

Some people mark the position of the inner tube relative to the tyre. Once you have found the hole in the tube, you can work out which part of the tyre is going to be the source of the puncture. Sometimes a sliver of glass is really hard to find, especially if the light isn't too good.

Edit: Cross-post! Scalped by Davidc.

 

[youngoldbloke]

Some people mark the position of the inner tube relative to the tyre. Once you have found the hole in the tube, you can work out which part of the tyre is going to be the source of the puncture. Sometimes a sliver of glass is really hard to find, especially if the light isn't too good.

ALWAYS do that, and don't put a new tube in until you have either found whatever caused the puncture still embedded in the tyre, or the hole/cut left by whatever caused the puncture. I carry a pair of fine pointed tweezers to remove the culprit.

 

[fossyant]

La la la.

Cycle punctures are a simple fix. Ride home and spot a screw stuck in the car tyre. Guess who goes to sit in ATS on Saturday Morning. My car but missus has been using it as hers has no air con.

Stop moaning .

 

[Davidc]

Some people mark the position of the inner tube relative to the tyre. Once you have found the hole in the tube, you can work out which part of the tyre is going to be the source of the puncture. Sometimes a sliver of glass is really hard to find, especially if the light isn't too good.

Edit: Cross-post! Scalped by Davidc.

You're forgiven!

 

[slowmotion]

ALWAYS do that, and don't put a new tube in until you have either found whatever caused the puncture still embedded in the tyre, or the hole/cut left by whatever caused the puncture. I carry a pair of fine pointed tweezers to remove the culprit.

If you don't have tweezers, a medium size safety pin works quite well when "excavating".