2013 XTX MPI Supercharger High Elevation Clutching

[MNBlizzard]

I need help in getting my sled ready for the mountains. I have a 2013 XTX 1.75 with an MPI 180 Supercharger. I am looking to run out west between 6500' and 9000'. I have an Ulmer stage 2 clutch kit installed and it works really well for low elevation. Any one have an Ulmer clutch set up that works well? I also have a set of new yamaha 8HG weights and rivets that came with my original SC kit.

Specifically, I'd like recommendations on:
Primary Spring?
Primary Weight?
Rivet - Outer?
Rivet - Center?
Rivet - Inner?
Secondary Spring?
Roller?
Helix?

Thanks!

 

[sheetwright]

FYI ulmer helped dial in the higher elevation sleds for yamaha. Might want to give him a call. Being you bought his clutch he might walk you through changing it from low to high etc. just my .02

 

[Sask Attak]

Post what you find out. I have a 2010 xtx with the mpi s/c and was wondering the same thing

 

[MNBlizzard]

Still searching...sent emails to Ulmer, MPI, and Yamaha; no one has replied. At this point, I am probably too late to order Yamaha MTX clutch weights and likely will have to try and adjust when out West next week.

In general, does one increase clutch weighting for elevation increases?

 

[mysledblows]

Generally speaking as you go up in elevation you go lighter, but with the blower you shouldn't have to really worry about anything. Heck the last couple years I took my NA 4 strokes out to Cooke and the Horns I didn't bother with the clutching. The couple hundred r's off peak aren't really noticeable unless you are in perfect snow/conditions and ride there all the time. For the Midwest guy going out for a few days I'd just ride it. Especially with the blower. Just turn the boost up and make the same power there as here at home.

 

[MNBlizzard]

^^^^I called the dealer in West this afternoon and they basically said the same things; thank you for your reply. I'll bring my weights with just in case I want to make adjustments.

 

[MNBlizzard]

Well, the real world proved differently. My first day at about 7000' I found my max rpm was off by about 2000. I run Ulmers clutching using the Supertip weights. I ended up pulling all the weight out of the tip and 6 grams out of the heel. That got me pretty close to perfect at the higher elevations. Moral of the story, you will need to remove weight even with the blower at higher elevation.