When to replace a tyre?

veganrun

So my hybrid commuter got its first puncture today. I’ve had it since March and had no issues and came out of work this evening to find the front wheel was flat.

I noticed a small piece of glass stuck in the tyre and I pulled it out but it seems to have cut the tyre. I’m under the weather so not in the form for wrestling the bike at the mo but I’m wondering how bad does the cut have to be before replacing the tyre itself?

Arthurdaly

If the cut is large enough to cause a small bulge when the replacement tube is pumped to optimal pressure then I'd probably dump it. You could place a patch on the inside of the tyre to cover the cut.

The problem will be that grit and other debris can get through the cut and cause a puncture. If I have considerable mileage (5000-6000km) and the wear indicators are well worn then I will bin them after 3 or 4 punctures.

srsly78

Upgrade to tougher tiers now and save yourself grief in the future. I did this after digging out a 3 inch shard of glass that was embedded in my back tire. Dublin streets are pretty rough! Schwalbe marathon plus are what I upgraded to.

veganrun

This was a small piece of glass, like a small pebble. I’m assuming that’s what cut it but haven’t had a chance to look at it.

The tyres are Michelin ProTek and they seemed to be good enough I thought.

smacl

veganrun wrote: »

This was a small piece of glass, like a small pebble. I’m assuming that’s what cut it but haven’t had a chance to look at it.

The tyres are Michelin ProTek and they seemed to be good enough I thought.

Worth checking your tyres every few commuting days for small embedded bits of glass and the like. What happens is you pick them up one day and they take a few days to get pushed through to give you the puncture. This small bit of preventive maintenance can save you a fair bit of roadside stress.

veganrun

Yeah good thinking. Those tyres have been bulletproof, at least compared to my road bike. I came out of work last night and saw the flat wheel and had to push the bike the whole way home as I had no pump or anything to repair it. I was feeling so sick yesterday that I wouldn’t have had the energy anyway to repair it. Thankfully it was less than two miles.

Stupid question but if you are going to change tyres do you need to change both at the same time? I’m not sure how many miles I’ve done on them. I’d say around 500 anyway. I’m just not sure if this cut in the tyre is going to just grow and/or let more stuff in. With the tyre deflated it was easy to pull it open.

smacl

I usually buy in pairs to save on postage but just replace the worn one which goes out to pasture to spend its final kms on the turbo.

crosstownk

veganrun wrote: »

I noticed a small piece of glass stuck in the tyre and I pulled it out but it seems to have cut the tyre.

When you take the tyre off, check the inside of the tyre to see if the cut has gone right through to the inside - yes, the glass may have pierced it but the protection layer may not be cut/torn. Cuts and small gashes are par for the course in the outside rubber part of the tyre.

As said earlier, regularly check your tyres for small shards of glass and use a pick to remove them. They get lodged in the tyre without breaking through the inside carcass but if left there long enough there's a good chance they'll cause a puncture in he coming days/weeks.