Mystery flat??

Schoie81

Anyone any ideas? 24miles on the bike last Thursday. Since then its been stood still and hasn't moved an inch. Yesterday (Monday) all was fine, came to it this morning and the rear tyre is as flat as a flat thing. The bike hasn't moved, and it doesn't seem like a slow puncture as the tyre was still hard at 2pm yesterday, but its gone completely flat overnight.

Should I suspect someone in the office is playing pranks? Or is it possible that something in the tyre sat there for a few days before finally going through the tube, even though the bike hasn't moved? Haven't take the tube out to look for the offending hole yet, but will be doing at lunchtime...

sungod

i'd guess prank

diamonddog

Blow it up and see if it is a puncture, if so check for the usual suspects in the tyre, check the valve and surrounding area. If it's not punctured then it's probably as you say some plonker at work.

Schoie81

I'm so stupid sometimes! I was just gonna whip the tube and look for a hole - never even occured to me to pump it back up first and see if it goes down again....

Definite puncture - i've got what I would describe as a 'graze' in the sidewall of the tyre, just above the rim. What could cause this? Only thing I can think is when I hit a big pot-hole, but that was over a month ago and i've cycled miles since then? Could that have done it though? But if the pot-hole damaged the tyre, why would that cause a flat weeks later - and almost a week after the bike was last ridden? Is it likely the tyre has had it now and needs replacing?

zingaiya

I've had a couple of cases of spontaneous inner tube failure while the bike has been hung up on the wall.

I've had it happen at a triathlon between T2 and picking the bike up afterwards (in both tyres).

I've also had it happen at a triathlon between the start and T1. Guess how annoyed that made me...

In all cases they were Bontrager inner tubes. Checked the tyres every time and they were fine, inside and out.

craker

I've just had a tube go at the valve join. Went flat overnight, took it out for inspection, pumped it up - no puncture. Put it back in. Pumped it up (hard), only started leaking air audibly when the valve was pushed to one side slightly.

Moral of the story is... just put a new tube in. Every time I've thought pranksters were at work it's come down to old tyres and inners with too many patches.

Mikey23

Mine went on the front wheel after being on the turbo for several days...

Schoie81

Failed patch! New tube in and ready to roll again!!

reformedfatty

As regards graze on the tyre, check that the brakes are properly aligned to the rim. A friend of mine knocked their caliper during transit in the car and the top of the brake block would hit the tyre rather than the rim when the brakes were applied. Only figured that one out once it had eaten through the sidewall of the nearly new tyre.

Schoie81

reformedfatty wrote:

As regards graze on the tyre, check that the brakes are properly aligned to the rim. A friend of mine knocked their caliper during transit in the car and the top of the brake block would hit the tyre rather than the rim when the brakes were applied. Only figured that one out once it had eaten through the sidewall of the nearly new tyre.

Thankyou. I do quite regularly have my bike in the car with both wheels off and always check the brakes are lined up when I put the wheels back on. The 'graze' in the tyre corresponds exactly with the position of the pinch flat I got from hitting a massive pot-hole a month or so ago, so i'm pretty sure that's what caused it. Seems ok though and the inside of the tyre looks unaffected by it. As it was a pinch flat, I probably didn't check the tyre properly when I patched the tube and so never noticed the graze on the tyre at the time. Will just keep an eye on it now.