What is this in ounces? 1.4kg-cm2 vs 2.6kg-cm2

4 replies to this topic
  • vchssrider

Posted December 15, 2005 - 03:06 AM


What are the weight in onces for the GTR-Y flywheel weights. I'm currently looking for flywheel weight for my 04 YZF450. Not sure which one or what weight to go with though. Currently ride A class in HS in VA.

  • sirthumpalot

Posted December 15, 2005 - 07:56 AM


Let me show you something really really cool. Go to google, and type in :

convert 1.4kg to oz

And you get this:

1.4 kilograms = 49.3835467 ounces

Are you sure you have the units correct? kg/cm^2 is pressure, such as tire pressure, etc.. Total mass would be just plain 1.4kg, and mass per volume would be 1.4kg/cm^3.

If they're telling you that the flywheel weights weigh 1.4 and 2.6kg, then those are some pretty honkin big flywheel weights.

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  • grayracer513

Posted December 15, 2005 - 08:42 AM


The GYT-R flywheels are listed as to their inertia mass compared to stock, not their actual weight. Inertia mass has to do with the actual flywheel effect, the amount of energy they store in operation. This is a more accurate way to compare flywheels in a way. For instance, the welded ring types will have a greater inertia mass than the same added weight simply bolted on because of the location of the added weight.

But it doesn't help much in comparing the GYT-R line to Dr. D's does it? Fortunately, Dubach has this information. The lighter of the two GYT-R flywheels is about 5oz heavier than stock, and the heavier "off-road" one is around 7.5oz heavier. Both the GYT-R and Dr.D are weighted by welding a machine ring to the OD of the stock flywheel, and balancing it afterward, and as such, the added weight provides the maximum amount of added inertia. Both are excellent products.

When comparing bolt-on weights to welded-on types, figure that the bolt on needs to be 3-4oz heavier to have the same effect.

  • vchssrider

Posted December 15, 2005 - 02:31 PM


How do you like the 8oz flywheel weight? I have ridden my bike the last two years without one, but I don't seem to be as fast as I was on my 99 YZF400. Could be just getting old. Figured I will give a flywheel a try and see if it helps out at all. Thanks for the info on the weights.

  • grayracer513

Posted December 15, 2005 - 03:09 PM


On my '03, I see no reason not to use it. The '04 has a slightly more civilized power delivery than the '03 did, but they are pretty similar.

Adding the 8oz flywheel made the bike generally easier and more fun to ride, as I don't have to concentrate as hard on throttle control in the lower gears. I got the bike with a Dr.D 4oz, and frankly, I can't see the bike being really enjoyable with any less than that. Grabbing the throttle is now much more likely to produce hard acceleration and/or raise the wheel instead of ripping the rear tire out by the roots as if it were a bigbore 2-stroke. And, of course, it stalls less. For those who think it makes the bike slower, when I rode the Elsinore GP this year, the best that any other bike could do on the pavement was match mine on accelerating from 2nd to top end. Nobody pulled away from it. And in the dirt, I had much better bite coming off corners than a lot of people did.

I encourage people to try a Dr.D. The downside is that he wants yours in exchange (he'll wait until you get your new one), so you don't have two to switch between if you want. But the upside is that if you want to try a different weight, you just send the one you have back and he'll switch with you for free (you pay the freight both ways). I'd say try a 6 or an 8 on your '04. You'll be happy with one or the other, I think.

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