Sculptor7

My Trek 1.1 2010 roadbike needs to have the chain. chainrings and cogset replaced after only 1 year. I probably have a few thousand miles on it but it seems like a pretty short life for a drivetrain that has been continually lubricated and kept away from sandy gritty conditions. My old steel Fuji from the late 70s seems to be still in pretty good shape although I just did replace the chain. I bought it about 2 years ago so don't know how much total mileage is on it. Guess I am surprised that I have to shell out $160 or more after only one year's riding.
A magnet held to the gears indicates steel, not aluminum.

Nerull

Your gears are wearing so quickly because you aren't replacing your chain when you should. A worn "stretched" chain will damage your chainrings and cogset much faster than normal wear and tear. It's a good idea to check your chain for stretch every few hundred miles.

FastJake

+1 with what Nerull said. If you replace your chain often enough your gears will last a lot longer.

BUT with that said I'm willing to bet you got screwed on replacing the chainrings. Yes they do wear out, but it takes a long time and on a bike that new I doubt they were trashed. From now on periodically measure your chain with a 12" ruler. When a chain is brand new 12 links will measure 12" exactly. When it becomes elongated by 1/16" over a 12" span you should replace it. This will save you money down the road.

I was going to say that because your bike has a 9 or 10 speed cassette you'll tear through chains a lot faster. But the 1.1 is still 8 speed, correct? In that case you're lucky, because 8 speed chain is still the "normal" width and will not wear as fast as the narrower 9 and 10 speed stuff.

igknighted

Yeah, chainring seems a little excessive, but maybe not... new england weather is really hard on bikes, and with all the sand they used on the roads over the winter, a lot of bikes need that type of work, even bikes that haven't been ridden that long.

As for "a few thousand miles", that's really a long time for a cheaper shimano chain. With regular degreasing and proper lube, it's doable, but if you road 200 miles on a bad chain, then the cassette is probably shot, so the diagnosis seems reasonable. As mentioned above, the more often you check for chain wear, the quicker you detect it and the more of the drivetrain you can save.

Drew Eckhardt 

Chains get < 1,000 to > 5,000 miles depending on lots of things like rain and lubrication.

Steel cassettes last through 1-4 chains depending on whether or not you pro-actively replace chains as they stretch or rotate through a a set of 3-4.

The chain rings should be fine for a long time even when abused.

FastJake

+1

I neglected to mention that keeping your chain clean and lubed will make everything last a lot longer. Using a dry chain full of sand could certainly tear apart an entire drivetrain in that time.

fietsbob

Dirt is your enemy.. clean stuff.

prathmann

Seems very short to me as well. How did you determine that the whole drivetrain needs to be replaced? As others have mentioned, the usual way of checking for chain wear is to use a ruler held up to the chain to see if the pitch is still right at 0.5". Measured over a length of 12", the pins should line up exactly with the inch and half-inch marks on a ruler. Up to a deviation of 1/16" over 12" is usually acceptable while any greater deviation is an indication that the chain should be replaced. With only a few thousand miles on the chain and avoidance of gritty conditions I'd be surprised if it's even at the 1/16" elongation point, but it should be checked and replaced if it is. Do you do much riding in the rain? That throws far more dirt than usual onto the chain and can contribute to faster wear.

The cassette (cogs) are normally replaced when you notice that a new chain skips when run over the old cassette. If you can replace the chain and not have any skipping then the cassette is still ok. And chainrings normally last much longer than either chains or cassettes. I finally had to replace the large chainring on my road bike, but it was after 90,000 miles of use - almost entirely on that ring.

Nerull

Depends on just how worn the chain gets. I've seen chains left so long that at least one of the chainrings develops severe skipping with a new chain.

Sculptor7

My LBS said the chain was so stretched he could not even get a "reading". My inspection of the chainring and the cassette would lead me to believe that the chainring (at least the large ring) is really worn because at least one of the teeth actually comes to a point. It did not seem to me that there was any noticeable wear on the cassette although I might not have looked at it as closely. The bike is still shifting well with only a little hesitation (very little) occasionally but with no skipping. Love the bike and want to keep it in good condition. Probably should have been more attentive to cleaning and replacement of chain. Was using dry lubricant which frankly I don't really trust. Switching to "ProLink" or something similar which is a light but not dry lubricant.

dabac

Determining wear on sprockets/chainwheels by sight is quite difficult. There are often a few teeth that have different shapes to them in order to help with shifting. What you see as wear might just be a design feature.