09 nytro primary spring

[redrock]

looking to tone down rpm after engagement for lower speed bush trails.
have 14.5 rollers and yellow silver yellow spring what would be a slightly softer spring, engagement is good with 145 rollers but still harsh when going at slow speeds...thanks

 

[nytro11tom]

yellow pink yellow 3000 rpm engagement

 

[Schlick55]

Correct on the Yellow pink Yellow. If you are a bigger guy do NOT run an Ultimax belt, when it is under big load and doesn't back shift quick enough it just gernades the belt. With this setup just run the 8DN belt and let it slip a bit when it needs to. The mountian guys love the 805 belt, but they are spinning the track paddling through the snow. A 300 pound rider with a 144" track and 114 studs, the track is not spinning. I learned this on Gogebic at about 90mph when I pulled over into some snow to cool it off a bit. I posted my problem and a bunch of other guys chimed in on the Ultimax belt that had the same thing happen.

 

[mach9]

Correct on the Yellow pink Yellow. If you are a bigger guy do NOT run an Ultimax belt, when it is under big load and doesn't back shift quick enough it just gernades the belt. With this setup just run the 8DN belt and let it slip a bit when it needs to. The mountian guys love the 805 belt, but they are spinning the track paddling through the snow. A 300 pound rider with a 144" track and 114 studs, the track is not spinning. I learned this on Gogebic at about 90mph when I pulled over into some snow to cool it off a bit. I posted my problem and a bunch of other guys chimed in on the Ultimax belt that had the same thing happen.

If you're going to run an Ultimax belt you'll likely need to make an adjustment to the secondary. I think the 8DN is too hard and with the primary sheave faces being worn grooved, it should be clear. I'm set up for trail riding and had fun this year clutch testing. I don't ever want to go back to the rock hard 8DN.

 

[Schlick55]

Fair comment on the rock hard 8DN. What would you do on the secondary? I wanted to play with the primary and get that dialed in before moving on the the secondary. With no snow and one trip to the UP this year I didn't have a quarter of the miles I wanted to play with. Any advice on the secondary would be great.

 

[mach9]

Fair comment on the rock hard 8DN. What would you do on the secondary? I wanted to play with the primary and get that dialed in before moving on the the secondary. With no snow and one trip to the UP this year I didn't have a quarter of the miles I wanted to play with. Any advice on the secondary would be great.

Ok, here is my opinion.
Stock secondary setup is designed to hold onto the hard slippery 8DN.
If you throw on a softer belt the secondary grabs more.
So a simple adjustment is to take a 10 degree wind out of the secondary spring. One step at a time.
Cheers mach9

 

[caper7]

I used the xs 805 belt and it never lasted 500 miles and was toast .. I weight in 200lbs and mostly drive powder days if you can find any this year.. I found the yammi belts much better but i blew a few of those to mostly miler days and running 90mph plus for a little stretch and boom