I just installed a -4oz flywheel and I must say that for $120 it has the be the best bang for the buck. It's almost as easy to do as the Cam Mod and gives you alot more torque. People claim that the bike will have a tendency to stall alot easier but I haven't run into that problem yet.

I've never even heard of that mod. How does a lighter flywheel give you more torque?

lightened flywheel will make the engine rev faster....thats probably where the feeling of more power is at

http://www.trailtech.net/atv_flywheels.htm
There's a little explanation here on the site where I got it.

Also go to www.yfzcentral.com and search around and you'll see alot of positive feedback from duners on this mod.

Nice read-up, thanks. That about sums that up.