Fly Wheel Weights vs Performance

9, 11 and 13 oz FWW's - will I notice much difference between the 9 and 13oz?

Is there a direct relationship between weight and, say, stalling, so a 10oz FWW would likely stall 1/2 less often than a 5 oz weight?

Any negative effects on rebuild life - will it be harder on bearings etc. with a chuck of metal on the end?

In my personal experience, there is a big difference in the 9 and 13, but there is no half-life type of correlation between stalling. I ran a 13 fww once along with being geared down, and the bike was like a big ol' 600cc 4 stroke in terms of easy power roll-on. Now I run the lightest Steahly fww for nasty snowy tight riding.

11 0z here, waste of money, maybe the 13 makes a diff?

they are stall prevention - I'd go big. Be aware that trials bikes use FWWs measured in pounds vs. ounces so I can't see any negative effects to engine longevity.

#1 the Steahly crew are the bestest to work with. They wipped out a custom weight for our dirttrack 125 mod in no time. I use the fw wieght for straight a way traction , smooth the Zing some ,and use the stored energy to run him in the corner hard even if he lets off early ( crew chief trick #347, i have lots more :bonk:

Go heavy ,try it out , they will take some off for almost no charge.

A F/W weight does twist the crank ,, more than without one. Better worded : a F/W weight does put some ammount of tortional stress on the crank . BUT we have never had any issues in the least running one at very very high rpm in our yz85 or the yz 125 with proper maint.

I can notice my 8 ounce fww on my bike. Tames it a little bit, improves traction a bit, and reduces stall a lot. I go back and forth with mine since they are so easy to take on and off..I should really have a heavier one, but I tend to leave it on all the time.

The Yamaha off road FWW rules hard. It's 8 oz. But it's all on the outside so it acts like a heavier one when you want it too and a lighter one when you don't.

And It's a single part that replaces you stock flywheel. You'll need a puller. But they're cheap.

Thanks for the replies.

I went for the 13 oz weight.

Called a few dealers too, Ballard's in Oz sponsored Glen Kearney when he raced YZ250's and they told me he used a 11oz weight. Pretty sure if Glen needed an 11, I'll need more than that!

Another poster just jogged my memory, will I need a flywheel puller to install the Steahly FWW on the YZ?

Another poster just jogged my memory, will I need a flywheel puller to install the Steahly FWW on the YZ?

no, it bolts to the outside of fw

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