is there a mileage guide as to perhaps clocking a certain number of km before replacing the tires or are there visible signs which tells one that the tire is in need of a replacement? will using worn out tires damage the rims or perhaps even the bike? currently using the race x lites .. dont really know how see the wear on the tires

Because different materials are used for tire tread, and of other variables like rider weight and riding style, it's very difficult to suggest how many km/miles you can expect from a tire.

As a rear tire wears the tread will disappear. It will become obvious. As long as the casing is intact, the sidewalls are not fraying and you're not flatting, you can still ride safely. If you're unsure about your tire wear, ask a knowledgable friend or your LBS to inspect it for you.

The most reliable signs of end of life are a bulge somewhere on the tire, indicating serious carcass failure (rare), a cut more than ~3mm in the carcass that exposes the tube, or visible carcass through the rubber tread. The latter usually occurs after an inadvertent brake lock up and skid. All presage imminent sudden tire failure. Worn out tires produce damage by causing flats and crashes. Check the whole circumference of the tire periodically for cuts, thin areas and bulges. Rear tire wears 2x the rate of the front. Steve

Hmmmm, would you then recommend rotating tires on occasion?

ThanX!

I have heard mtb riders say that this is a no-no becuase you can't recover from a front wheel washing out, but often you can recover from a rear-wheel skiding out. however...grip doesn't really decrease for a road tire as it wears...I'm just confusing myself now...

hmmz i'm using road tires so theres no threads =|

Funny you should ask. I asked the same question elswhere just recently. For more replies and information, see:

https://groups.google.com/groups?dq=&...%26start%3D125

Actually tires on bikes are replaced more often because of cuts and damage than because they wear out. If you ride in a benign area then in theory you could rotate your tires and get a few thousand more miles by doing so. In practice it rarely works out.
I stopped doing it mostly because I thought for awhile 20mm tires were a good idea, ended up with a bunch and I use them on the front at least until I run out, down to one now. 23mm are my tire size of choice. Also spend about half my time on a bent. Stev

Woody's advice still applies. You can generally ride a road tire until you start seeing patches of threads (not to be confused with treads) through the wear surface of the tire. Then you're on borrowed time.

Regarding rotation, either you need to rotate often enough that the wear is about the same between front and back, or when the back one wears out, move the front to the rear, and replace the front.

I used to rotate tires on my commuter but I got advised from a real know-it-all that this is not good economy in the long run since a tire failure on the front can be life threatening. Better advuce; when it appears you need a new rear tire buy a new one, install it on the front and put the old front tire on the rear. As a general practise never install a used tire on the front.

I bought two Michelin Axial Carbon Pros last year for $28 each. My goal is to put 2,000 miles on the rear before replacement, and 4,000 on the front. I don't plan to rotate the tires, as many have recommended, because I'm too lazy. Right now, I am at 750 miles, with no flats. The front tire, thus far, shows very little signs of wear and no cuts. The tread on the rear has flattened out somewhat from its original shape, but no signs of cordsor cuts or anything. I am using Slime plastic liners to keep the thorns out. Thus far, the Michelins and the liners have been a good combination for me.

I have the same tires and have 2,700 miles on them since January with no problems whatsoever. Some cuts and the rear has flattened quite a bit, but no performance issues that I can tell.

I don't rotate as the rear wears faster and you should have the better tire on the front.

I have a WTB Nano-Raptor 2.1 on my mountain bike that has lasted more than a year and a half (at least 1k miles) and it's finally pooched. Not that the tread is dead, but simply that the tread's are flexing beyond traction. A tire that used to be the fastest dry tire made now spins out in the dirt. Oh well. It had a good run. I won't replace it until my new frame comes in (my Stumpjumper won't clear my Nokian tire )

I was on an organized day tour a couple of years ago. Several miles into the ride, I felt my tire get kind of lumpy.

Quick inspection revealed a growing bulge. I took the tire off to see what was going on and found that the tire was worn paper thin, but the cording was not yet showing. I lined the inside of the tire with a tire patch, but knew it would not last long.

No spares tires were available, so I proceeded with the ride. Just when I passed two old ladies out for a walk, KA BAAAM! the tire exploded. The tube poked through the tire, wore thin and then exploded. It was an enormous sound - very much like a big caliber gun shot. The old ladies almost jumped out of their skin. It shocked me too!

I THINK that you can at least try to inspect your tires once in awhile by taking the tire off and feeling both sides of the tire between your thumb and forefinger. It is worth a try, anyway.

If that happens, take a dollar bill and place it over the hole. Patch the tube and ride to the nearest LBS.

How do you patch a tube after a blow out? The tube is often shredded. I like the dollar bill solution though, does a twenty last longer?