Slow puncture or normal?

cormie

Hi,
I recently pumped up my tyres pretty well, and after 2/3 days of non use, I notice the back one has gone kinda flat (unrideable for sure) while the front is ok. I pumped it up again and left it for a day or two again and it was fine, then I went for a cycle and pumped it up fully before I left, now 2 or so days after that cycle I see it's flat again.

I read here before that it's normal for a racer to lose pressure like that, but is this too much to quick or is it normal? The front tyre is still fine by the way.

Unless the POS aldi pump damaged the valve or something? I replaced the aldi pump with a much better joeblow or whatever it's called

niceonetom

yes, you have a slow puncture. replace the tube.

blorg

A bit of pressure loss would be normal, but only over a week or two, not 2/3 days. And it would still be rideable. And you would expect front and rear to be the same. So as niceonetom suggests you need a new tube.

cormie

Thanks for the replies. Would it not still be ok to use on short cycles of an hour or two? It lasted fine for a 2 hour cycle after I pumped it up the last time.

With something like this, would you folk replace the tube or patch it up? When would you patch instead of replacing? Just to get you home until you can replace the tube, or until the patch gives way? How many patches would you use on one tube, when would the tube have had its day?

Gavin

cormie wrote: »

Thanks for the replies. Would it not still be ok to use on short cycles of an hour or two? It lasted fine for a 2 hour cycle after I pumped it up the last time.

Unfortunately not. Bicycles have been known to explode if the tube has a slow puncture. Happened to one of those Tour de France riders when he was on his fixie headin up the alps. Got blown right off the side by the force of the explosion. Be careful man !

Gav

kenmc

Tis true. The rubber degrades into a hydrogen gas, all it takes is a little tiny spark like from a stone hitting the rim or something. Boom.

beans

My bike lives under my stairs, and one night while watching telly the front tube exploded. All I knew was something from the direction of the kitchen had blown up, and peeked around the door-frame gingerly, fully expecting to see a hole where the cooker was... put a jump across my heart I can tell you.

So yeah... exploding tires, they do sometimes just go boom

blorg

You can patch a tube as much as you like and it will last forever, if patched properly it is as strong as the rest of the tube. There are some punctures you can't patch, especially if they involve the valve. However tubes are so cheap that many just don't bother. A slow puncture will also be difficult to find (as the hole will be small) but should become apparent if you dunk the tube in a bowl of water.

I would tend to patch depending on my mood and the weather (or obviously if I had used up my spare tube already.) Once patched I would leave it alone, no need to change it.

cormie

thanks for the info

Anywhere to recycle old tubes?

kerry4sam

OP - it's the valve thats damaged by the sounds of it and how you are connecting the pump that the problem i'd say ... just go easier the next time with it.

kerry4sam

cormie wrote: »

thanks for the info

Anywhere to recycle old tubes?

For recycling the tubes cormie ... Just gibe them to some plumbers you might know ... They come in real handy when transporting pipes etc on the roofs ... The tubes hold the items in place for them

cormie

kerry4sam wrote: »

OP - it's the valve thats damaged by the sounds of it and how you are connecting the pump that the problem i'd say ... just go easier the next time with it.

This was my suspicion, I got an Aldi pump that I think bent the little bit on top of the valve :mad:

The new pump I got is fine though!