Mountain Biking - Problem with casette

Yo everyone this is sorrta a continuation of previous post by JasBike about my rig.

So i've pretty much narrowed it down to the rear casette and it looks like its bouncing around and it obviously shouldnt be (i did this by riding and watching the rear of the bike and it seemed to be popping around all over the place making my bike vibrate all the way into the handlebars). Any suggestions on how to secure it?

is it a threaded cassette? If so, just tighten it. (if you have a chain whip) If not, your LBS will do it for you.

You mean this one?: http://bikeforums.net/showthread.php?t=53607

Anywasys,

I need a bit more explanation as to what the problem is. When pedaling does the chain jump around and fail to "grab" a gear? Does this happen all the time or just under high torque situations?

How old is the bike/chain/cassette?

7, 8 or 9 speed cassette? IOW, the cogs on the wheel are there 7, 8 or 9 cogs?

L8R

http://bikeforums.net/attachment.php?attachmentid=13084&stc=1

Hopefully the picture works thats the first time i've tried~
Anyways its a 7 cog casette, bike was purchased in 2000 so i figure its around that year's model (i wasnt very serious about biking then otherwise i'd know) only major overhaul is the LX front derailleur everything else is stock. Oh and i hate my LBS they try to rip me off..often -.-. The rattling vibration happens primarily when im over any terrain other than a paved driveway.

O.k., forget about the noise for now, I think I know what that is.

What I'm more concerned about is, "Will it stay in a gear, or does it jump around?"

L8R

I'm betting thats a freewheel on there and not a cassette.

If it is a freewheel, virtually any freewheel wobbles quite a bit on lower end bikes.