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woodracer1162

What flywheel weight should I use?

21 posts in this topic

I ride an 07 yz450f mainly on trails and wood races. Everyone who has rode my bike or that I have talked to has told me I needed a flywheel weight. What size would be the best for me?

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I just added a 13oz to my 426. It has been a great improvement. I wouldn't go any lighter than that if you are mainly in the woods, mine still wraps crazy fast. If you ever do want to go to the track the weight is easily removed.

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You won't need to remove it. I run a GYT-R Off-Road flywheel (9oz). IMO, the bike just should have been built with it. All upside, no downside.

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You won't need to remove it. I run a GYT-R Off-Road flywheel (9oz). IMO, the bike just should have been built with it. All upside, no downside.

I agree 100%(as usual) with Gray on this subject. I have one on my 08 and it was a huge improvement off the bottom. One of the biggest gains for me personally is how well the bike hooks up now. I am running a rear starcross tire that easily would've done nothing but spin on my old 04(without FWW) and the tire is still getting good drive even when coming out of a corner hard.

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I ride an 07 yz450f mainly on trails and wood races. Everyone who has rode my bike or that I have talked to has told me I needed a flywheel weight. What size would be the best for me?

"the heavier the better" if you truly spend most of your time in the technical woods. Enduro and Hare Scramble racers will often buy a real heavy weight, then machine down until they find their "sweet spot" in managing rpm's

I have a whopping 15oz in my KX500, and absolutely LOVE it, but it's not a fair comparison (a KX500 vs. a YZ450F)

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I've run a few, and based on overall gearing, fitness conditioning and trails each have helped quite a lot. Having said that, the 9 would be my choice for overall riding.

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You won't need to remove it. I run a GYT-R Off-Road flywheel (9oz). IMO, the bike just should have been built with it. All upside, no downside.

That's what I use and love it.

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The auto clutch and a flywheel weight accomplish two different things.

I have both and love the combo.:thumbsup:

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The auto clutch and a flywheel weight accomplish two different things.

Yes, I am well aware of that.

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Has anyone tried one of the Hinson Steel overweight clutch baskets yet ? I see they are marketing them as an alternative to the FWW. "Get a stronger clutch basket with the effect of a FWW".

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It would be stronger, but there won't be any noticeable addition to the engine's rotating inertia.

This comes up every time someone suggests that the extra weight of a Rekluse obviates the need to install a flywheel. The steel basket (or Rekluse) is heavier, and it does have the advantage of having a larger diameter than a flywheel does, which increases the effect of its rotating inertia.

However, the clutch rotates at only 38% of crank speed, and speed contributes exponentially to inertia, whereas mass only linearly. Furthermore, the inertial force from the rotating clutch is delivered to the crank through the primary drive gears, which are a 1:2.652 overdrive ratio going that direction, which reduces the force to 38% of whatever it was at the clutch.

There is a little truth to the statement, enough so that it isn't totally bogus, but it might as well be BS.

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Does anyone make a flywheel for the '09 450 that is heavier than 9oz? I have the Steahly 9 oz on mine, but I'm thinking I'd be better off with a little bit heavier one. I ride technical off-road / woods.

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Does anyone have any experience with the weighted steel clutch plates? Moose claims that they add 12oz of flywheel "like" effect.

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Does anyone have any experience with the weighted steel clutch plates? Moose claims that they add 12oz of flywheel "like" effect.
See my post above. Sounds like a great way to get you to buy something that costs less to make as if they were "special".

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It would be stronger, but there won't be any noticeable addition to the engine's rotating inertia.

This comes up every time someone suggests that the extra weight of a Rekluse obviates the need to install a flywheel. The steel basket (or Rekluse) is heavier, and it does have the advantage of having a larger diameter than a flywheel does, which increases the effect of its rotating inertia.

However, the clutch rotates at only 38% of crank speed, and speed contributes exponentially to inertia, whereas mass only linearly. Furthermore, the inertial force from the rotating clutch is delivered to the crank through the primary drive gears, which are a 1:2.652 overdrive ratio going that direction, which reduces the force to 38% of whatever it was at the clutch.

There is a little truth to the statement, enough so that it isn't totally bogus, but it might as well be BS.

Thanks for taking the time to type that... really, thanks...

So now I am taking from what you are saying that if someone installs a Rekluse where you can't stall.... that you are going to rev higher and the clutch is going to slip more... and when you have full engagement and it's really ripping, delivery and traction would still be smoother with a flywheel weight...

And if you had a flywheel weight + Rekluse it would end up being set differently to avoid a stall, not rev as much or slip as much... delivery would be smoother and traction would be better...

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That's about right. If you use both, you get the advantages of both, in combination, rather than overlapping, so to speak.

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You won't need to remove it. I run a GYT-R Off-Road flywheel (9oz). IMO, the bike just should have been built with it. All upside, no downside.

I've had this on my '07 for about a year now. Like Gray says, all ups and no downs.

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That's about right. If you use both, you get the advantages of both, in combination, rather than overlapping, so to speak.

grayracer,

As it has turned out, I haven't been able to get anyone to give me time of day on making a flywheel weight or heavier flywheel for my application.

So, do you think it would be worth the coin to go with one of those heavy steel baskets?

I still want to do the Rekluse at some point anyways... just wondering about the heavy baskets like Stealthy and Hinson offer...

Thanks.

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