strange punctures

[goon]

Had a few strange punctures in front wheel recently,so need to know if I have the correct wheel/tyre/tube set up. The bike is a Dawes streetlife hybrid,it is fitted with 700c x35 tyres ,the tubes I use are 700 x 28-38 which assume to be correct but when fitting the tube it seems too big and have to push in slack. This may be causing the tube to bunch up or twist under pressure (80 psi on presta valve) the bike originally had semi knobbly tyres and schrader type tubes but cannot recall what size was on the tyre.

 

[apollo179]

Had a few strange punctures in front wheel recently,so need to know if I have the correct wheel/tyre/tube set up. The bike is a Dawes streetlife hybrid,it is fitted with 700c x35 tyres ,the tubes I use are 700 x 28-38 which assume to be correct but when fitting the tube it seems too big and have to push in slack. This may be causing the tube to bunch up or twist under pressure (80 psi on presta valve) the bike originally had semi knobbly tyres and schrader type tubes but cannot recall what size was on the tyre.

Im no expert but everything looks ok. If your getting a recurrant puncture in any wheel the obvious thing to check is that you havnt got a thorn etc sticking through the tyre. Correlate the location of the puncture to the corresponding position on the tyre and have a good look - there may be something in the tyre that isnt isnt immediately noticeable just by running your thumb over it.

 

[Holdsworth]

It could be that you are pinching the tube between the tyre bead and the rim each time, also make sure that you a little air in the tube when pushing it into tyre and then when the tyre is on, check that you haven't caught the tube before you pump it up.

 

[Angelfishsolo]

Where are the punctures? On the top, side or bottom of the inner tube. This is the biggest clue as to the cause. as your inner tubes are designed to cover a range of tyre sizes with a max greater than yours it is understandable there will be some slack. Putting a little air in the tube before fitting the tyre helps a lot.

Edit :Holdsworth beat me to the punch on the air but as it is good advice twice is better than not at all.

 

[cyberknight]

Have you changed valve type?

Sounds like you have unless i misread, this could be causing rubbing on the rim due to different thickness of the rim hole and valve thickness.

 

[lulubel]

It could be that you are pinching the tube between the tyre bead and the rim each time, also make sure that you a little air in the tube when pushing it into tyre and then when the tyre is on, check that you haven't caught the tube before you pump it up.

+1

I have 700x25c tyres, and I'd have to push in my 18-25 tubes if I didn't put any air in them. With some air in (and it only needs to be a little), they naturally assume a rounded shape and sit nicely inside the tyre. Then you just need to go round both sides of the wheel before you fully inflate, checking there's no tube trapped between the tyre sidewall and the wheel rim.

The other thing I've been told to check when I've had recurring punctures is that your rim tape isn't damaged. Run your fingers round the wheel when the tyre's off to make sure there aren't any sharp bits poking through where the spokes join that could puncture the tube.

 

[Angelfishsolo]

+1


The other thing I've been told to check when I've had recurring punctures is that your rim tape isn't damaged. Run your fingers round the wheel when the tyre's off to make sure there aren't any sharp bits poking through where the spokes join that could puncture the tube.

This was a reason I asked where the punctures were