some_guy282

I have some new tires (about a month old) and yesterday got a flat rear wheel while heading home. I was only about five blocks from my house so I decided to just ride home on the flat. Upon fixing the flat I discovered a small section of the sidewall bulging out. Could I have caused the bulge from riding on the flat, or is it more likely a defective tire?

I_bRAD

ya think?

rmfnla

Did it bulge before you rode on it flat..?

some_guy282

geez, was it really such a stupid question?

The only type of damage I've ever heard warned against with riding on a flat before was damaging the rim. I figured only five blocks going slowly would be no big deal.

I_bRAD

5 blocks walking doesn't sound like a big deal either.

some_guy282

Not when you live in my neighborhood. Every other house has two hoodlums hanging out on a stoop.

I_bRAD

Well I guess you should be happy that:

• You didn't damage your wheel (hopefully)
• You made it home alive

I bet you'd have a hard time outrunning the bad guys with a flat anyhow!

Rowan

I've ridden some distance on flatted tyres of all sorts, and haven't damaged the casings, except one that was 15 years old and the sidewalls were perished anyway.

However, the bulge might simply be that you haven't seated the bead of the tyre on the rim properly after fixing the puncture. Deflate the tyre, check around the rim and bead, and inflate again. You don't state exactly where the bulge is located, which makes diagnosis difficult.

Having posted the thread, however, I wouldn't bother pursuing any thoughts of "defective tyre".

urbanknight

In general, it's not a good idea to ride any length on a flat clincher, but it's on on a tubular. If the tire bulges out even after pumping it up, I'd take it easy on corners or get a new tire.

some_guy282

Planning on getting a new tire. You live and you learn...

Michel Gagnon

To answer the original question:

– Riding on the flat didn't cause a bulge by itself.

– What kind of flat was it? Maybe you broke the casing while you got your flat. In other words, if you had repaired the flat right away, you might have discovered that the tire was ruined anyway.

– Riding on a flat tire creates a crease. You create pressure points where the rim tries to cut through the tire and a little further away where the tire is folded flat. If you ride long enough, you'll cut the wire and could end up with a zipper cut*. So if your tire had a lot of mileage, you might have accellerated something that would have happened a few months down the road anyway.

– If you ride on a few crevasses with a deflated tire, you have the risk of flattening the rim or doing a snake bike in the tube.


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* The zipper cut happens when truck tires have been run for a few hundread kilometres at very low pressure and are then repaired. They may have a weakened casing and will litterally rip apart at mid-height in the shop, soon after being repaired. The same isn't likely to happen with a bike tire, but you see the imagery.

some_guy282

There was a small puncture in the tube. I couldn't find whatever made it still inside the tire.

On the inside of the tire where it is bulging, the rubber from the tire is peeling away and you can see the wire bead underneath.

The tires are Continental Globetrotters BTW. They're a new model touring tire that are supposed to be puncture resistant.

San Rensho 

Its toast. I've ridden a couple of blocks on a rear flat, but I put as much of my weight on the handlebars to get the weight off the rear. Not a good idea, but better than nothing.