Mystery of inflated tubes

ZaWing

Hey,
I have a problem with my front tubes, what i just dont understand. I've now punctured 3 tubes and they all repeat the same pattern. They get an oval pattern of small pokes, which only a few are all the way through, on the opposite side of the valve (outer part).

Ive checked the tyre for any sharp things etc and the wheels are quite new Campagnolo Zondas. The tyres stay normal for about 10-50km, everytime different distance and they go totally flat. Any ideas guys?

Garry H

Check for cracks or splits on the inside of the tyre

ZaWing

Garry H wrote:

Check for cracks or splits on the inside of the tyre

The tyres are spotless and relatively new. The oval ring is always in the same spot..

svetty

Sabotage?

schlepcycling

Does the rim have spoke holes?, if so make sure the rim tape covers each hole completely.

ZaWing

schlepcycling wrote:

Does the rim have spoke holes?, if so make sure the rim tape covers each hole completely.

Ive been thinking about rim tape but since the wheels are Campagnolos G3 design and they said it doesnt need rim tape, since theres no spoke holes. Plus the hole pattern is on the outer part of the tube, opposite side of the valve. Maybe i should contact Campagnolo or buy new tyres, if its any help..

schlepcycling

Are you wheels the 2 way fit version, if so you can run them tubeless and get rid of the inner tube altogether....problem solved.

ZaWing

Its the normal clincher version

slowbike

Easy way to test if it's the tyres or the spoke holes ...
put some tape over the holes and the area of the tyre where the holes are occuring.

put the tube back in the tyre and pump up
Go for a ride
once home, remove the tube and inspect the tape - you should see the indents where the problems are occuring.

sungod

are you sure that this isn't being caused during the (short) time you're riding on the flat tyre?

maybe there's something holing the tubes elsewhere, and the oval patch is a aside effect of riding flat rather than the initial cause of deflation (you can check by sealing that area and then see if the tyre leaks elsewhere)

ZaWing

Thanks for the answers so far! Im running pressure of about 90psi (im thin like a rope). Does the tape thing help since the holes appear on the outer part of tube, opposite of the valve?
Could the valve hole or something be the problem and cause the ring of holes (its an oval ring of about 3cm diameter running center along the valve)? Its been now 4 tubes and they all repeat the same exact pattern. I fix the holes with a patch and a ride later theres more holes in the ring. Tubes are Continentals Race 28.

drlodge

Not 100% sure where these holes are - on the outside of the inner tube where the valve is? The holes must be caused by whatever is pressing against that part of the inner tube, so it would be the tyre. Is there a small sticker on the inside of the tyre? Closely inspect whatever is pressing against that part of the inner tube.

A photo of the offending tube would help.

ZaWing

Ive checked the tyre numerous times with a flashlight and the inside and outside is very clean. Ive installed the tyre back in different positions so its not always the same than before.
Tube number 4, ive marked it with a marker

drlodge

That looks really odd, more like a manufacturing defect.

ZaWing

Thought about the same thing but its been one vittoria tube and a few continental ones.. I guess its our cat thats poking the holes, because cant figure out any solutions.

homers_double

It's in direct alignment with the hub mounted garmin sensor isn't it?

My guess is the magnet in the sensor is attracting the microscopic steel fibres in the innertube and one has developed artificial intelligence and is trying to escape.

As I said, my best guess...

drlodge

Are the tubes like that fresh out of the box, or does the pattern appear only when they've been on the wheels?

That pattern is directly opposite the valve, as though whatever is being used to pump the tyres up is going through the valve and hitting the tube causing the pattern.

ZaWing

drlodge wrote:

Are the tubes like that fresh out of the box, or does the pattern appear only when they've been on the wheels?

That pattern is directly opposite the valve, as though whatever is being used to pump the tyres up is going through the valve and hitting the tube causing the pattern.

Their like that after a while on the wheels. Im using a basic Lifeline trackpump.

crankycrank

Try and match the spot on the tyre with the puncture next time it happens. Possibly a thin spot in the casing. Switch the tyre to the back to see if it still happens. I've never seen this before so just grasping at straws but eliminate the variables as much as possible.

drlodge

crankycrank wrote:

Try and match the spot on the tyre with the puncture next time it happens. Possibly a thin spot in the casing. Switch the tyre to the back to see if it still happens. I've never seen this before so just grasping at straws but eliminate the variables as much as possible.

+1 It has to be the tyre, the wheel or something to do with the inner tube...so eliminating variables is key. I have no idea what is causing this by the way. However my gut says, because it is right opposite the valve it has something to do with that, but I have no idea what.

Rotate the tyre 180 degrees and see if that makes any difference. You could also then try putting a thin piece of paper between the inner tube and the tyre to see if any kind of imprint is left.

ZaWing

crankycrank wrote:

Try and match the spot on the tyre with the puncture next time it happens. Possibly a thin spot in the casing. Switch the tyre to the back to see if it still happens. I've never seen this before so just grasping at straws but eliminate the variables as much as possible.

Sorry for the long looong answer. Had a busy work week and a holiday abroad.

So i switched the front tyre to the back, put a sparkling new inner tube and drove about 70km and boom, same thing.

After the "magic puncture" the tube is no longer round and as a "sinkhole" (even before the patch)

ZaWing

It has to be the wheel/rim. I think the only thing to do anymore is to return the wheels and talk to Wiggle..

keef66

ZaWing wrote:

crankycrank wrote:

Try and match the spot on the tyre with the puncture next time it happens. Possibly a thin spot in the casing. Switch the tyre to the back to see if it still happens. I've never seen this before so just grasping at straws but eliminate the variables as much as possible.

Sorry for the long looong answer. Had a busy work week and a holiday abroad.

So i switched the front tyre to the back, put a sparkling new inner tube and drove about 70km and boom, same thing.

After the "magic puncture" the tube is no longer round and as a "sinkhole" (even before the patch)

Your original issue was with front punctures. Are you saying you have switched tyres front to back and still got a front puncture? Or is this latest one a rear puncture, which would suggest it's the tyre at fault. (But you also say you've rotated / refitted the tyre, yet the punctures are always opposite the valve)

This is all very X-Files...

ZaWing

Your original issue was with front punctures. Are you saying you have switched tyres front to back and still got a front puncture? Or is this latest one a rear puncture, which would suggest it's the tyre at fault. (But you also say you've rotated / refitted the tyre, yet the punctures are always opposite the valve)

This is all very X-Files...

I switched the front tyre to the back and got the same front tube puncture.. so it has to be the rim some how..

keef66

ZaWing wrote:

Your original issue was with front punctures. Are you saying you have switched tyres front to back and still got a front puncture? Or is this latest one a rear puncture, which would suggest it's the tyre at fault. (But you also say you've rotated / refitted the tyre, yet the punctures are always opposite the valve)

This is all very X-Files...

I switched the front tyre to the back and got the same front tube puncture.. so it has to be the rim some how..

Well that is pretty weird. I'm at a loss to explain how the rim could be causing punctures in the part of the tube it doesn't touch...

Is the valve hole unusually small so the valve stem is shaving bits of metal off as it vibrates? Can you wrap a bit of electrical tape round the valve stem? Any rough edges there?

DeVlaeminck

Nothing stopping the tyre seating correctly in that part of the rim is there? Which bit of the tyre do you fit last - if it's the bit by the valve maybe try fitting that first?

Alternatively is the valve hole big enough - it's not catching on the valve somehow is it and forcing the tube into the tyre- or you've not done something mad like leave the little spinny round nut thing on the valve but inside the rim?

DeVlaeminck

I'd like to see a more detailed picture if you can - no marker just a hi res close up.

ZaWing

DeVlaeminck wrote:

I'd like to see a more detailed picture if you can - no marker just a hi res close up.

crankycrank

I'll take another stab at this. When you install the tube do you push the valve stem in the tyre to make sure the rubber is not caught under the tyre bead? The fact that the unmounted tube doesn't expand at the valve area as much as the rest of the tube is normal by the way.

pinno

Posting a nothing reply just to see where this one goes.

it might be a case for Monty Dog.

Harry182