Stock chain and sprockets, when should I replace them?

[armysig]

I have a 2004 400EX. No mods to the engine, but I just recently did some A-arm and axle relacements.
I would like to know the average life of a chain and sprocket.
I'm a novice MX'r so I'm thinking I should do this some what on a regulare base.
I have noticed a little slack in the chain since I have made my quad wider, and I fixed that by adjusting it on the swing arm. I have kept the chain clean and well lubed since I have owned the quad and this is the first that I have the stretch.

[Randy H]

for your sprocket's..if they are sharp and pointy at the top and bent foward a little bit..its time for new sprocket's..if you really need to you could tourn them around..for your chain if you could move the links side to side and its streached long ways its time for a new chain

[Rip_Tear]

if it's time to change one change them all.

[Randy H]

not always..but for the front sprocket and chain yes..but the front sprocket turns alot more than your rear sprocket...so your rear sprocket will still be fine

[armysig]

Thanks for the advice guys. The front sprocket should be good. I had put on a 13tooth about 12 months ago. But I guess if I do one part of the system I should do the entire set up.
Does anyone have some advice on what brand or company I should look at when purchasing the parts?

[04'400ex'er]

DID X-Ring ATV chain is a very good chain and Sidewinder makes good sprockets. You will be ok with most any STEEL sprocket though...

[awsomeaussies]

So a steel sprocket is better? Because I've noticed that the aluminum sprockets are more expensive, so I thought they were just better to use.

[Wandell]

Aluminum is lighter, but steel last longer. I just trail ride with mine so I bought one of the cheap steel Primary Drive kits from Rocky Mountain ATV. I got front and rear steel sprockets and an o-ring chain.