Flywheel Weight Won't Budge.

Hello All.  I need some help.  I bought a 1993 YZ250 that I am rebuilding.  There is a nice Steahly flywheel weight that came with the bike, but it will not budge.  The weight doesn't have the center nut, but the two 1/4-20 holes.  I built a nice jig to take the weight off.  I have used everything in my arsenal to try to take the weight off, including an impact wrench, which only bent the 1/4-20 screws.   I am thinking that the previous owner used kryptonite on the threads.  I haven't figured out a way to put heat to it or any kind of penetrating oil.  I am hoping that someone smarter than me has the answer.  All answers will be tried....twice.

Would you mind adding photo? Not sure, but thinking you just need a flywheel puller.

It looks like this, only no center threads.   Sorry, I'm away from the engine.  I have a flywheel puller, but the weight is blocking access.


Edited by GoVols

Humm. Only thing I can think is to try spraying the base of the bolt heads with penetrating oil and using heat. If the bolts were installed with loctite red, the heat will loosen that bond.

The one in the picture has set screws on the outside edge. If yours is like that you have to loosen those. Impact wrench helps to.

The 1/4 -20 bolt holes only go down as far as to get the bolts threaded.  Due to the holes location, penetration oil would never reach.  I'm not sure where to apply the heat to release the locktite.  

Possible PO sent flywheel to Steahly and they used some industrial strength bonding agent on the screws. I know they bond some of their weights without screws.

I e mailed Steahly, I hope they have an answer.  Thank you so much for you help.


Yep the previous post shows how it comes off.  You bolt the tool to the flywheel weight then turn the tool with a wrench.

dont try running a bolt into the center hole and push on the crank.

The weight is its own nut.  It spins off not pulled off.

I know some of those weights are a " glue on ".  Heat would probably be the answer in that case...    

I had one on a 250 and it did not pull off it screws in the threads of where the fly wheel goes in so back it off to the left on the sides I think mine had alen screws to stop it from backing off

unscrew the 4 set screws on the edge of the weight. Use your tool to unscrew the flywheel weight. Should just unscrew from crank

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