Anyone know how much an '06 stock flywheel weighs?

I was trying to find a +9.21oz GYTR flywheel (on backorder everywhere) when a fellow TTer PMed and said he had one for sale that he had bought, but never installed, because he had sold his YZ. I specifically checked with him to ask if the one he had was the heaviest one ( adds 9.21oz) which is part# GYT-2S297-50-50. He confirm that it was, so I bought it from him.

Well, I got it in today and noticed that the install instructions which came with it are for the GYT-2S297-50-00, which is the lighter (+4.8oz) version. Now I'm confused, maybe disappointed.

The part itself is stamped F2S210 and weighs in at 23.2 ounces (658 grams). Does anyone know what a stock flywheel weighs or have one lying around (after you upgraded) that you could weigh and let me know for comparison purposes? If a stock one is 14 ounces, I'm good to go. If it's 18.4 ounces stock, I got sent the lighter one.


I have a stocker. I'll weigh it this evening.

I have a stocker. I'll weigh it this evening.

Muchas gracias senor.

you are correct.the 9.21oz fw will weigh in at 23.04oz.mine did.the stock fw off my 08 450 weighed 13.79oz,or 12.57 troy oz.

13.5 is what I got. Scale is probably trustworthy within an ounce or less.

Excellent. Thanks very much guys.

Any tips/hints/suggestions on installing this thing? I did get the correct flywheel puller from Rocky Mtn. Will I likely need to get a new crankcase cover gasket?

Not likely, but possibly.

New flywheel successfully installed. The Tusk puller worked like a champ.

Thanks for all the help guys.

good sure and post your thoughts on the flywheel once you get a chance to go for a ride..

good sure and post your thoughts on the flywheel once you get a chance to go for a ride..

Hopefully, that will be tomorrow morning (before it gets too darn hot).

BTW, where in Texas are ya?

DFW area...heading to Nocona tomorrow morning to ride!

What about yourself?

Tyler. Maybe sometime we can meet up at Buffalo Creek MX. I'm not very track-savvy (especially when it comes to jumping), so I can use all the help I can get.

Took the YZ out early this morning to Mud Creek ATV park (2000+ arces near Jacksonville). I was the only bike out there. They have a mix of trails (hard, sandy, muddy), some of which are just for the 4-wheelers who love mud. I pretty much had the trails to myself from 8 until about 10:30.

:):thumbsup: on the heavier flywheel. It makes a significant difference in the way power comes on in the low end. The YZ never stalled even the times when I was slogging it through a foot of muddy water. That change, combined with the 51t rear sprocket, makes the YZ quite capable on the trails. When I got it home, I had to scrape the mud off the fender bottoms and front frame area with a plastic putty knife while spraying with the hose.

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