F4 Upgrades Help
 

I recently bought a 2010 Cannondale F4 and am looking to make a few minor upgrades to the drivetrain. I've been biking for awhile but I have to admit I do not know much about parts and upgrades.

Right now the bike has all Deore components. I've popped my chain off the crankset a few times on bumpier terrain and am thinking about upgrading the rear derailer to an XT possibly to help prevent this in the future. Besides this problem, I'd also like to make the bike faster. Weight savings are important but so is reliability and cost.

Since my budget is pretty limited, my questions are: Will upgrading the derailer solve the problem? Do I have to upgrade the shifters as well? And would my money be better spent upgrading the crank/bracket to lose some weight?

One final question, if I do decide to get an XT derailer, how do I know which one to get? There are 6 different product numbers on Shimano's website.

Thanks for your help.

When does the chain pop off? When you are shifting up to the big ring in the back? Does it just jump off any ring? If it jumps off any ring while going over bumpy trail, maybe the chain is to long. Does it skip. Have you tried to adjust the cable and derailuer stops? I think if the chain comes off this derailuer, it will come off another. Let us know whats happening