Cam chain troubles

[bikr003]

Was riding in this morning when i noticed my engine was making a funny sound when down shifting. Kyle took me to this biker shop and the guy said its my cam chain. I would rather do it myself and get some experience. Has anyone done it before who can help me out? give me a few pointers! hopefully i just have to tighten it rather than replace it

[dino3310]

don't know FA about the GPX but my old DR's got a manual adjuster, very easy to adjust. get a hold of a bike manual for the GPX you'll find all you need to no in there plus you've got the pictures to go by which make it easier.
if yours has the automatic adjuster that could be buggard or the cam-chain has stretched to its limits,you might have to leave it for a mechanic to sort.
i would question the cam chain theory as you would have noticed it getting louder over a period of time as the chain stretches i don't think it would have happened between rides.