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I have a 20 SS XTR. Looking for info from anyone whose installed the heavy flywheel on a 19+ SS. I ride mostly east coast trails. Will I notice the difference with the heavy flywheel? I’m reading mixed things online. Some saying it doesn’t make much of a difference in the SS for low speed which is mainly why i’m considering it.
 

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Not really be able to go any slower with it in a SS. Slow speed is limited by clutch disengagement which kinda occurs at a speed and rpm where the heavier flywheel may not be so different. You will notice it mellow the engine out a bit on acceleration and make it smoother feeling going through the gears. It may help it carry itself through sand or something at low speed where it may have pulled rpm/speed down and disengage otherwise.
 

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I've not tried it, but I would expect a bit less acceleration and engine braking due to more mass. This may or may not be better.
 

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I've not tried it, but I would expect a bit less acceleration and engine braking due to more mass. This may or may not be better.
If you just let of the gas the flywheel momentum will carry the rpm longer.

More flywheel mass can also increase engine braking if you are down shifting. Downshift and now the heavy flywheel provides more braking because takes more to change the rpm of the heavy flywheel especially if engine drops rpm much during the shift. Harder to spin it back up so more braking occurs.
 

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If you just let of the gas the flywheel momentum will carry the rpm longer.

More flywheel mass can also increase engine braking if you are down shifting. Downshift and now the heavy flywheel provides more braking because takes more to change the rpm of the heavy flywheel especially if engine drops rpm much during the shift. Harder to spin it back up so more braking occurs.
I

I agree with your first point. I'm not sure about your downshifting point though. More mass will make the flywheel more resistant to slowing down to match the lower gear. I think the clutch would have to slip a bit more.
 

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I

I agree with your first point. I'm not sure about your downshifting point though. More mass will make the flywheel more resistant to slowing down to match the lower gear. I think the clutch would have to slip a bit more.
Relhok,
Just thinking out loud as I am still stock weight on my 19 SS SE but it just seems like that would have to be the case.
See if I can better explain the way I am thinking about it. ??

This is why you are missing it I think.
The engine doesn't slow down when you downshift. It speeds up.
Let off the gas and drop a gear. The engine rpm goes up. If It has to do that against more flywheel weight then I believe you will have increased braking. I don't have to tell you how fast downshifts occur with the SS. It is quick. Clutch don't slip much is just winds up the engine each time you downshift if you were scrubbing speed with the engine braking instead of all foot braking.

Just like it is slower for the engine to accelerate with heavy flywheel. It would be harder for the driveline and rolling momentum to speed up the heavier flywheel when you force it to happen quick by downshifting. It may slide the tires if you pull two gears lower for same reason. It can't take the heavy flywheel from 5000 to 9000 as quickly as if it had a lighter one. Like the light one would have less resistance to rpm change and would rev up more quickly.

You still have your 19 ? How is it doing these days ? What front diff # you on ?

Man you were/are rough on that car. Lol.
 

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Relhok,
Just thinking out loud as I am still stock weight on my 19 SS SE but it just seems like that would have to be the case.
See if I can better explain the way I am thinking about it. ??

This is why you are missing it I think.
The engine doesn't slow down when you downshift. It speeds up.
Let off the gas and drop a gear. The engine rpm goes up. If It has to do that against more flywheel weight then I believe you will have increased braking. I don't have to tell you how fast downshifts occur with the SS. It is quick. Clutch don't slip much is just winds up the engine each time you downshift if you were scrubbing speed with the engine braking instead of all foot braking.

Just like it is slower for the engine to accelerate with heavy flywheel. It would be harder for the driveline and rolling momentum to speed up the heavier flywheel when you force it to happen quick by downshifting. It may slide the tires if you pull two gears lower for same reason. It can't take the heavy flywheel from 5000 to 9000 as quickly as if it had a lighter one. Like the light one would have less resistance to rpm change and would rev up more quickly.

You still have your 19 ? How is it doing these days ? What front diff # you on ?

Man you were/are rough on that car. Lol.
What you're saying is true and makes perfect sense, provided the clutch plates can perform the job equally against the added flywheel weight. The plates are sourced from the 1300 V-Max muscle bike so maybe they can. I don't know.

No more broken diffs with dgarris' 4-spider design. I rode all the way out of the trails in diff-lock with a broken rear axle. I'm curious to see the parts fiche of the new larger RMAX front diff with steel housing...
 

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I had a heavy flywheel on my 2016, I noticed that it tempered the zip of the YXZ and I did not like it at first. However, I got used to it and used it for a couple of years. After that I removed it, and enjoyed the zip that was lost.

Now, with my 2019 SS I have not used it and I have hit lots of rough west coast terrain just fine over 6600 miles. However, I have seen a couple of 2019 SS owners with heavy flywheels that have really enjoyed it. If you get the Hess two piece setup, it will be much easier to install and remove if you don't like it or want to change it in/out depending on the terrain.
 
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