Small Air Cylinders

[majordad]

Wife has bought one of those tiny compressed air cylinders. She says they mend punctures, do they ? I think all it does is reinflate the tyre/tube after you mend it.

[ewenm]

You're right.

[Rich_W]

And CO2 also leaks out of inner tubes. (slowly though) So you'll need to refil with normal air at an appropriate time. Probably not during the race

[Simond S]

unless she bought one of these

http://www.halfords.com/webapp/wcs/stores/servlet/...

[Raven Flyer]

I have the Decathlon equivalent of that Halfords stuff. £3.99 in Decathlon and works well for mountain bike tyres. I have had a tyre stay fully re-inflated for 6 weeks, before getting a new tube.

Would be no good for a road bike due to the pressures involved.

[majordad]

Raven you've hit the nail on the head. She did in fact buy it in Decatalon last month. It says recongre on the clyinder as well as air so maybe it will repair a puncture. She has a MTB on the standard MTB Conti Tyres with inner tubes, I wonder would it repair a thorn etc prick. If it does work I d get one myself as a get you home device. She rides 95 % on Tarmac.

Thanks for the replies.

[Raven Flyer]

Yep, they work perfect for a thorn repair and once you have put it in the tyre, it will stop further thorn punctures... within limits. If it's a 2.2 tyre or bigger, it will need topping up from a bike pump to be fully up to normal pressure. Riding on under inflated tyres will cause pinch punctures which the contents won't fix.

Better still is to put slime tubes in, in the first place.

[majordad]

Re these slime tubes, say you get a puncture, how do you know you have one if they seal it. Does the slime not gum up the valve ?
And why do some bikes have presta valves and others schraeder , is one better than the other on a bike by a lot ?

[Engineer1]

Slime can gum the valve so you need to be careful which orientation the valve is in, slime will plug a puncture if you get one, it is good enough you just need to keep an eye on the tyre pressure. Shrader verses Presta seems to come down to how easily you can alter the tyre pressure.