Inner tubes

[Yanto]

Strange question I realise, but is there a 'best before date' for inner tubes? I bought 5 Schwalbe tubes about 18 months ago and have not needed any of them until today when I had a puncture. Replaced the tube and pumped up to 100 psi. Checked bike about 2 hours later and tyre flat again. Nothing inside tyre, so replaced tube again, and after an hour it had gone down again! Now either I have bought a dodgy batch of tubes or I am doing something wrong when inserting the new tube into the tyre. Any advice please as I am baffled! Cheers

 

[on the road]

Is the puncture on the top of the tube or underneath (the part that sits on the rim)?

 

[Yanto]

Seems to be close to the valve each time. Could I be pinching the tube, or fixing the tube to the rim too tight before fully inflating?

 

[HLaB]

I read one maintenance book where it author said tubes could go 'off' but the author stays in California where temp might be an issue. I've never had a problem my self and I tend to go a long time between uses of the spare, touch wood.

 

[Yanto]

Yes this is the first time in 18 months that I have had to change a tube!

 

[on the road]

You need to inflate the tube very slightly before putting it back in. If it’s near the valve, then I assume its underneath, possible cause could be a protruding spoke nipple, or maybe like you said it is a bad batch.

Maybe you could try a different brand of tube, see what’s that’s like?

 

[Yanto]

otr - thanks. Think I'll buy some new ones

 

[on the road]

Yanto, you don't happen to have an aero rim by any chance?

 

[Yanto]

otr - wheels are standard Bianchi Componenti Ambrosio

 

[MessenJah]

You need to inflate the tube very slightly before putting it back in. If it’s near the valve, then I assume its underneath, possible cause could be a protruding spoke nipple, or maybe like you said it is a bad batch.

Maybe you could try a different brand of tube, see what’s that’s like?

Alternatively it could be caused by a hole in the rim tape.

Or something too small to find without a magnifying glass is stuck in your tyre.

Both happened to me a few months ago.

 

[on the road]

The only reason I asked is because I have the same problem and only two nights ago I pumped up my tyre and it went down, took the tube out and noticed it split at the valve. But the reason I have my problem is because of my aero rims, as I’m pumping up my tyres the valve is moving from side to side because of the shape of the rims and stressing the area around the valve, eventually it gives way and splits at the valve, it's very difficult the hold the valve still while pumping.

Suffice to say, I won't be getting aero rims again.

 

[MessenJah]

What brand are the rims?

 

[on the road]

Mine are Mavic CXP33 rims.

 

[Yanto]

Mine are Bianchi Componenti Ambrosio

 

[MessenJah]

Mine are Mavic CXP33 rims.

Oh! I was gonna buy some of them. Similar to the rims I use now but not as deep. Apparently they're 'deep section' rims not 'aero' rims, because they're not deep enough to provide an aerodynamic benefit.

Are you sure it's not just your pump that's causing the damage? I know quite a few people who use cxp33's, and none of them have had valve splittage problems.