Kurt's Polaris 850 Clutch Kit Review

[tmberro]

I installed and ran Kurt's new clutch kit for the 850 over the weekend on my sled. I've been looking forward to this kit since I decided I would not turbo my sled this year and would only run a gear down and Diamond-S TI can. The kit consists of: custom twin trax helix for high or low elevation, primary spring, weights, and two delrin washers.

I put 500 mountain miles on my 850 with the stock clutching before this clutch kit. I always thought the stock clutching was okay - wasn't all that impressive, but got the sled around. IMO really lacked bottom end.

Kurt's clutch kit was a major performance improvement. First thing I noticed on the way in to the riding area on the trail was how responsive the sled was now. I could easily blip the throttle and spring the sled off of the big moguls in the trail to double and triple them. Off trail the sled was overall easier and more fun to ride than stock. The throttle felt like it was connected to the track - mash the throttle and the track was instantly reacting. This gave me more confidence popping off drops, crossing creeks, and turning uphill from a side-hill almost anytime I wanted. The back shift was excellent also - letting off the throttle dipping between trees on a side-hill, or brake tapping in the air, the clutching was right there ready to take a hand full of throttle every time. I wasn't able to race a stock set up 850 up a hill (nor is that the reason I go mountain riding), but I felt faster in all aspects of my riding over the weekend.

In my opinion - worth the money. Curt hit a home run with this kit!

 

[tdblakes]

did you have to do any shimming for belt to sheave clearance?

 

[tmberro]

did you have to do any shimming for belt to sheave clearance?

Tom - No adjustment required. The weights provided are 10 series weights.

 

[WAsledder]

Are you running his gear down or pro pulleys?

 

[tmberro]

Are you running his gear down or pro pulleys?

I had pro gears on this weekend but have the Kurt's Polaris gear down kit waiting in the garage. Ran out of time last week.
Just comparing Kurt's vs. pro visually - I can see the advantage of running Kurt's. The belt is way beefier and the pulley diameter is larger which I'm guessing will result in lower rolling resistance and lower belt temps.

 

[mnach]

I had pro gears on this weekend but have the Kurt's Polaris gear down kit waiting in the garage. Ran out of time last week.
Just comparing Kurt's vs. pro visually - I can see the advantage of running Kurt's. The belt is way beefier and the pulley diameter is larger which I'm guessing will result in lower rolling resistance and lower belt temps.

Have you rode with the gear down kit installed yet? If so, What are your thoughts? Thanks!

 

[Scott]

Travis,
The stock Pro QD gears are lower geared than the stock Axys QD gears, right?
Do you know how many teeth are on each?
What are the ratios for each?

 

[tdbaugha]

https://www.snowest.com/forum/showthread.php?t=424354&highlight=pro+pulleys

 

[tdblakes]

Anyone run Kurt’s clutch kit in the UP? Wondering what weights I should use since their chart doesn’t go below 3500’. Thinking I’ll start with 10-68s but might have to go up to 70s?

 

[xpspenziv]

You stated 2 delrin washers are part of his kit. Secondary obviously. Why not just put the next stiffer spring?
Now you have no idea what yur pressures are. Do you know your installed height now that you shimmed it? Shouldn't be close to cool bind. Belt to sheave clearance?

 

[cdebodt44]

Anyone run Kurt’s clutch kit in the UP? Wondering what weights I should use since their chart doesn’t go below 3500’. Thinking I’ll start with 10-68s but might have to go up to 70s?

Sent from my iPhone using Tapatalk

 

[Wheel House Motorsports]

You stated 2 delrin washers are part of his kit. Secondary obviously. Why not just put the next stiffer spring?
Now you have no idea what yur pressures are. Do you know your installed height now that you shimmed it? Shouldn't be close to cool bind. Belt to sheave clearance?

They are maybe .050" thick tops, def no risk of coil bind. I have some I could measure, the idea isn't for generating preload is to help allow the spring to slip and rotate under compression/expansion more freely resulting in quicker smoother shifting. I personally run the thrust bearing behind the cup instead of delrins, but it works functionally the same and adds noticable function to the system.

 

[xpspenziv]

Yup. helps keep the spring from digging in. I file all the edges round on both ends of the spring. I also run the roller bearing. It does add a little to the preload and final. If I remember right it was like 5# at installed ht and 10# at final.