Bicycle Mechanics - When is a tire compromised?

I have 1000 miles on these tires. How do you tell when a tire has been compromised by road debris and should be changed?

How long do road tires normally last? I barely see any wear on these tires.

Rear tire:
http://img141.imageshack.us/img141/8461/img3217gh3.th.jpg (http://img141.imageshack.us/my.php?image=img3217gh3.jpg)

Front tire:
http://img248.imageshack.us/img248/2128/img3224yr3.th.jpg (http://img248.imageshack.us/my.php?image=img3224yr3.jpg)

That doesn't look like anything to me, unless I'm missing what I'm supposed to be looking at. As for when to retire a tire, check Sheldon's site.

There aren't too many cases of 'you have to replace that tire NOW!!!!', and most of those include situations in which the tire is bulging or something that indicates the tube is about to pop out. I don't see that on your tire. Other than that, you're talking about good old fashioned wear and tear.

As far as the amount of rubber goes, ride it till it's nearly threadbare if you like. But as the tire gets thinner you'll probably start getting more flats. When you get a new tire is then a function of how tolerant you are of changing flats.

To me, though, your tires don't look particularly worn. I see one minor cut in the tire. I would only replace that if it's gone all the way through the tire and actually sliced part of the fabric - look on the inside of the tire to see. If there's not a full cut, there's no reason to replace it. Even if there is, you don't have to replace it, but you might be more likely to get flats.

In general, 1000 miles isn't all that much for an average tire.

Thanks for those comments. I have been fortunate in that I have not had a flat on this bike since I got it in late August. Unlike my other bike that has had a number of flats in less miles.

Today I hit a personal high of 46.9 mph on a nice downhill. It would have been a bad time to learn that I should have replaced that cut rear tire before the ride!

I won't worry about them in their present condition.

That's no problem, it looks like the cut is only in the rubber. I'd just work some superglue into the cut. Shoe Goo is also good to plug holes in rubber. The cuts to worry about are the ones that go through the casing cord, those are usually fatal.

Al

That's no problem, it looks like the cut is only in the rubber. I'd just work some superglue into the cut. Shoe Goo is also good to plug holes in rubber. The cuts to worry about are the ones that go through the casing cord, those are usually fatal.

Al

Thanks Al.

I hope to avoid those fatal ones. ;)

Your rear will wear faster, look for a pronounced flat spot. When it's time, put a new tire on the front and the front on the rear.

Thanks capwater.

Now here's another question about tires. (I know I should do a search...)

How do I know what size tires I can put on my bike? It came with 700x25. Will 700x23 fit? Would I even want to go there? Or does it matter?

Yes, 23's will work. You will probably not notice a hell of a lot of difference; in fact, widths seem to vary widely among manufacturers. Your new 23s could look the same as your old 25s.

Ah. Sounds like the way clothes fit.

700c X 23 is actually the most popular road tire size.