CLUTCHING ANSWER!!!!

[YamahaTim]

Do you have to do anything special? Someone said shim something on the back of the clutch? Or can I just throw an 8dn on an see what happens?

While I had the secondary off I grabbed some washers and put enough in to have the belt ride just over the edge of the secondary. Like just the ribs above the lip. Tim how did you set yours?

Well funny thing is that the dealer did it for me. They are the ones who first put the 8DN on there. I have a picture of it on my thread, with the belt deflection showing. I would say around a 1/8 inch. See I broke four belts. So I was like there is something going on here! Fix this!!! So they did, the shimmed the secondary and put the 8DN in and now it rocks!
Wish I could take credit for trying that belt, but I guess I deserve it since it totally ruined the inside of my sled exploding 4 belts ruined everything in there. So I'm super happy they figured this out! Cause 100$ for 4 belts and 100$ for me to get there and back for gas. So almost 1000$ to get it fixed. Now the covered 3 belts and warranted my side panel and side belly pan and all the stuff around my break caliper. So I am only out 400$ in gas. But they did some extra stuff to make me happy. It's there again however. But that's another thread...

Can you guys tell I'm at home. Like I said if I can't snowmobile I want to talk about it...lol

 

[sxr70001]

Has anyone checked to see if the 8DN is fitting all the way down into the bottom of the primary. If so did it require any shims to get to the correct side clearance. Seems I remember it should be around .010 of an inch.

 

[YamahaTim]

Has anyone checked to see if the 8DN is fitting all the way down into the bottom of the primary. If so did it require any shims to get to the correct side clearance. Seems I remember it should be around .010 of an inch.

Take a look at my post, about using the 8DN. I put on there what you will need to do to put it on and have a picture to see the belt deflection.

 

[sxr70001]

I saw that Tim, but it doesn't really answer my question. If the belt is a different width something should have been done to your primary as well. Unless it's the same width belt and just a different length. Then that would make sense.

Thanks for sharing all your info so well.

 

[09nytro]

The belt is the same width , it's just 11mm longer that's it !

 

[stingray719]

The belt is the same width , it's just 11mm longer that's it !

And quite a bit thicker on the side (contact patch)

 

[YamahaTim]

I saw that Tim, but it doesn't really answer my question. If the belt is a different width something should have been done to your primary as well. Unless it's the same width belt and just a different length. Then that would make sense.

Thanks for sharing all your info so well.

It is a little bit wider, but the primary is the exact same primary from the Nytro. So the width should not matter. And my picture does not show deflection I got that messed up. It shows how high it sits on the secondary.

 

[stingray719]

I saw that Tim, but it doesn't really answer my question. If the belt is a different width something should have been done to your primary as well. Unless it's the same width belt and just a different length. Then that would make sense.

Thanks for sharing all your info so well.

It is a little bit wider, but the primary is the exact same primary from the Nytro. So the width should not matter. And my picture does not show deflection I got that messed up. It shows how high it sits on the secondary.

And set like that the deflection was perfect as far as I was concerned in mine.

 

[YamahaTim]

Ya I think so too, I have a lot of hard miles on the belt so far and works great! Just need to take a tiny bit of weight out, cause I'm a little low on the rpm.

 

[stingray719]

Ya I think so too, I have a lot of hard miles on the belt so far and works great! Just need to take a tiny bit of weight out, cause I'm a little low on the rpm.

Mine is holding steady at 7800 and seems to run very well, 8DN brought it down from 8200 to 7800...thats alot of belt slippage on Viper belt. Of course I want to get it up near 9k but 7800 seems to be full torque. But remember full hp starts at 8200 and flattens alot so don't expect big numbers adding a few hundred rpm over 8500 peak hp. Interested in hearing result though.

 

[YamahaTim]

Ya I think so too, I have a lot of hard miles on the belt so far and works great! Just need to take a tiny bit of weight out, cause I'm a little low on the rpm.

Mine is holding steady at 7800 and seems to run very well. 8DN brought it down from 8200 to 7800...thats alot of belt slippage on Viper belt. Of course I want to get it up near 9k but 7800 seems to be full torque.

The 1049 has a broad torque band, so a little under 8800 would be fine. But if it's only 7800 you are leaving some power on the table! You would want to be 8750-8900 for max power.

 

[MrSled]

Ya I think so too, I have a lot of hard miles on the belt so far and works great! Just need to take a tiny bit of weight out, cause I'm a little low on the rpm.

Mine is holding steady at 7800 and seems to run very well. 8DN brought it down from 8200 to 7800...thats alot of belt slippage on Viper belt. Of course I want to get it up near 9k but 7800 seems to be full torque.

The 1049 has a broad torque band, so a little under 8800 would be fine. But if it's only 7800 you are leaving some power on the table! You would want to be 8750-8900 for max power.

With a turbo you want it close to the rev limiter 9000 to 9100 if you can....

 

[stingray719]

Ya I think so too, I have a lot of hard miles on the belt so far and works great! Just need to take a tiny bit of weight out, cause I'm a little low on the rpm.

Mine is holding steady at 7800 and seems to run very well. 8DN brought it down from 8200 to 7800...thats alot of belt slippage on Viper belt. Of course I want to get it up near 9k but 7800 seems to be full torque.

The 1049 has a broad torque band, so a little under 8800 would be fine. But if it's only 7800 you are leaving some power on the table! You would want to be 8750-8900 for max power.

Agreed, gong to get there. But unlike a 2 stroke I am not that far off max hp. My calculations or guess was 130hp at 7800 and 137hp at 8500....or something...lol

But as I ride lots of powder I want to get near 9k so those deep powder days I am still turning above 8500.

 

[YamahaTim]

Right on...that's what I'm going to do. I have some real small rivets that I'm going to take out and that should be perfect 8900 rpm. Or I'll change my helix.

 

[09nytro]

Why does the 8dn pull the RPM'S down so far , and it's not from slipping because I had mine clutch pretty good and how I'm taking a lot of weight out of it and still not where it needs to be .
It's just not adding up