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Hey all
A 19c Continental on a Shimano RS-50 front wheel keeps puncturing tubes (looses air in a matter of hours).
Cannot for the life of me find the cause so any input would be useful, so far I've done the following:
Gone through 3 new inner tubes
Spent 20minutes under a spot light checking the tyre for any debris or splits, inside/out/sides - nothing
Gave the wheel and rim a further check - nothing
But to no avail!
I'm close to using a different wheel but I refuse to be beaten!
Thanks
Are you noting the position of the puncture (e.g. relative to the valve)? Makes it a lot easier to narrow down the location to a small area on the tyre..
Is it puncturing in the same place every time..?
Look harder!!
Before you take the tyre off mark where it is relative to the valve, that way you can isolate where to focus your search by matching up with where the hole in the tube is. I've had splinters of glass/flint/whatever that buried themselves into the tyre carcass and really needed teasing out
Where is the puncture hole located?
I've had that with a riml where the weld had cracked. Every time I hit a bump, pothole, cattle grid etc, I embed up with a flat. Might be worth checking for that or for burrs on the rim itself.
Also, I had this recently on one road innertube with a removable valve core. I found the air leaked from the core over a matter of 24hours or so - I removed the valve core, put some superglue on it then screwed it back in.
Check rim rape, check rim inside for any sharp edges/badly finished metal.
squashing the tube between rim and tyre when you inflate?
Is someone playing games with you?
Check rim rape, check rim inside for any sharp edges/badly finished metal.
I expect that would sting...
I have had this problem; I eventually traced it to a sharp piece of glass embedded in the tyre carcass and I suspect that when the tyre was in contact with the road it deformed puncturing the tube.
haha I think someone really is playing games with me!
Will have a another good check again later. It is puncturing in the same location, with the relevant location being checked on the tyre, but nothing there...odd.
Will report back..
cheers
My spate of mystery punctures turned out to be the brake blocks misaligned so they were just above the rim and were touching the side wall of the tyre. Ruined 2 tyres including a brand new one. Just made a horizontal slit just above the bead.
Had a customer with a similar problem this morning, seems like he was pinching the tube with tyre levers whilst fitting it.
My serial puncturing was caused by the rim tape being forced into the spoke holes exposing the rim of some of the holes. The edge of the spoke hole would then pinch-flat the tube, or the tyre would let go when sat in the workshop or just after being re-inflated! Replace the rim tape if it has deformed into the spoke holes in the rim.
cheers for all the replies people.
Will venture into the garage tomorrow to try out your suggestions, will give an update - how exciting hey! 😉
The solution is as follows: stop prancing around on the road bike and get out on the MTB. Haven't got an MTB at Uni? No excuse, sort it out.
I had the same problem as Sandwich some new cloth rim tape sorted it for me.
I have had this problem; I eventually traced it to a sharp piece of glass embedded in the tyre carcass and I suspect that when the tyre was in contact with the road it deformed puncturing the tube.
I've had this also.
I have had this problem; I eventually traced it to a sharp piece of glass embedded in the tyre carcass and I suspect that when the tyre was in contact with the road it deformed puncturing the tube.
I have had this as well
take the tyre off and turn it inside out. You might see it then