Need help ID'ng flywheel?

Sounds weird huh? Well, here is my story. I bought my 99 YZ400 used from a guy who mainly rode it in the woods. I know he told me it had an 8 ounce flywheel weight on it. I mainly ride motocross and would like the bike to have a little more snap so I decided to yank off the flywheel weight. Now I was staring at it and I am wondering if in fact it has a flywheel weight on it at all. It looks like it does but having never seen what a stock flywheel looks like and looking at the picture in the manual, I'm pretty sure it does have a flywheel weight on it. What I am looking for is confirmation. The reason I think it has a flywheel weight on it is because there are 4 small allen head screws around the outside of the face of the flywheel. I was hoping that after I took them out, the weight would come off but apparently I need to pull the flywheel off to get it off. I got the flywheel nut off but I don't have a gear puller or flywheel puller. So before I go out and pick one up and yank the flywheel, are the 4 allen head screws a tell tale sign of a flywheel weight on this bike? On my CR500 that was the setup but the flywheel weight came off when I removed the 4 allen screws. Somebody please give me some insight before I puddle up...

Thanks in advance,

Pat :)

Yes it has a weight on it. They go on the inboard side of the flywheel on the 400/426.

Flywheel pullers are cheap and it comes off easy but getting it back on you need an impact wrench.

Be careful as I've heard the you can damage the crank or strip it.

Might be worth a few $ to have a pro put it back on, should only take him 5min.

Thanks F-pilot, after reading your post and taking a look at again, it all makes sense. First time I've seen a flywheel weight on the inboard side.


Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now