Bicycle Mechanics - road bike tire worn out?

How do you know the tire you have is worn out and is no good anymore? I had a flat tire but i tried to fix it. Everything came along fine but the tire gets out of the frame from one particular side. I do not know if its worn out or if i am not putting it in right. I need your insight. Thanks

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Obvious indications are an extremely squared off tyre and multiple punctures that canno be attributed to tube installation error or trapped debris that is not located.

I run my tires until the cords show though or there is a gash that could allow the tube to peek though and rupture. Sounds like you didn't get the tire on the rim properly. Deflate and try again, the tube is most likely poking out a little and causing the sidewall to stick out.

For road bike use. rear tires will show the casing threads through the rubber when worn to (or a bit past) the replacement point.

Front tires basically never wear out as they are much more lightly loaded and don't absorb the driving forces. I've weighed front tires with 7000 miles on them and they weigh within 10 grams of their new weight and showed no tread wear. That doesn't mean they can be used forever. Aging, flexing, light exposure, etc. do damage the rubber and I replace the front tire every second rear tire.

Some riders "rotate" their tires by swithching them front to rear to even out the wear and replace both at one time. I prefer to keep the thicker tread tire up front the entire time.

I've worn plenty of front tires down to the cords, takes about three times as long as a rear though using 23c medium performance type road bike tires and the way I ride.

If the tire bead isn't staying inside the rim it can be that it isn't placed ("seated") properly all around, or that the tube is bunched up a bit at that spot, or that the rim or tire is damaged. You should deflate the tire and pry it open and make sure the tube inside is more or less straight. and that it is fully inside the tire, especially at the valve, where the tube is reinforced. You should be able to push the valve stem partly into the rim to make sure the valve stem base is well inside the tire bead (reinforced tire lip). Also inspect the metal rim to make sure it has no dents or bulges.

As you reinflate the tire, keep checking that it is evenly placed all around the rim - there may be some seam or coloured section that you can use as a guide, that needs to be the same distance from the rim all the way around.

I've worn plenty of front tires down to the cords, takes about three times as long as a rear though using 23c medium performance type road bike tires and the way I ride.
Hmmm, I'm using the same size and tire type and the fronts really show nearly no wear after many thousands of miles. As I mentioned, I do change them with each second rear tire or at about 6,000 mile intervals for most brands of tires.

I suppose if I really persisted I could wear one noticably but it hasn't happened to me yet.

Hmmm, I'm using the same size and tire type and the fronts really show nearly no wear after many thousands of miles. As I mentioned, I do change them with each second rear tire or at about 6,000 mile intervals for most brands of tires.

I suppose if I really persisted I could wear one noticably but it hasn't happened to me yet.

What kind of tire? Flintstone?;)

I get about 1500 miles or so out of a Continental GP or similar.:)

What kind of tire? Flintstone?;)

I get about 1500 miles or so out of a Continental GP or similar.:)

I am running Hutchinson Fusion 2 tires. They have about 2300 miles on them. Front is still good, back is squared off but no cord showing yet. I would guess they would easily go 3000 or more, but I always change them in the off season.

What kind of tire? Flintstone?;)

I get about 1500 miles or so out of a Continental GP or similar.:)
Well, you buy boutique tires! Wadda ya expect. :)

Actually I get about 2500 - 3500 miles on a rear tire as long as nothing like a bad cut or large puncture kills it off prematurely. I've been using Vittoria Rubino and Rubino Pro lately and they seem to have about the same life as my earlier experience with Performance's house-brand Forte and some lower line Michelins. I'm fairly light (~150) so that does help.

Hmmm, I'm using the same size and tire type and the fronts really show nearly no wear after many thousands of miles. As I mentioned, I do change them with each second rear tire or at about 6,000 mile intervals for most brands of tires.

Why not move the unworn, but aging, front tire to the back and put a new tire up front? You'll save a tire every 6000 miles.

Why not move the unworn, but aging, front tire to the back and put a new tire up front? You'll save a tire every 6000 miles.

I don't really see any reason to do this. Just incurring extra labour. It's not like aging does anything to the cords.