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Ulmer Racing Stage 2 Clutch Kit

DMCTurbo

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Joined
Nov 12, 2005
Messages
2,753
Age
50
Location
Val Caron, Ontario
Country
Canada
Snowmobile
2017 Sidewinder XTX LE 137
I see Allen is now offering a stage 2 clutch kit, includes STM weights, primary and secondary springs and a helix.
 

so the other day I was out trying my sled with the Powertrail flash. just curious how my rpm compares to yours? I am currently running Ulmer's clutch kit(60ys) from last year with 2 tungstens on the outer tip and 2 washers on the inner hole, my rpm on acceleration is 9150 and settles at 9050 rpm.
 
so the other day I was out trying my sled with the Powertrail flash. just curious how my rpm compares to yours? I am currently running Ulmer's clutch kit(60ys) from last year with 2 tungstens on the outer tip and 2 washers on the inner hole, my rpm on acceleration is 9150 and settles at 9050 rpm.
Similar however I ran the 35/39 reverse and it pulled the rpm down a tad to 8900ish
 
so the other day I was out trying my sled with the Powertrail flash. just curious how my rpm compares to yours? I am currently running Ulmer's clutch kit(60ys) from last year with 2 tungstens on the outer tip and 2 washers on the inner hole, my rpm on acceleration is 9150 and settles at 9050 rpm.
You may want to add a gram to pull the rpm down 100 or so, I'd try 1 washer in the middle hole. Ideally with pt you want to be 89-8950ish from what Ben told me last year.
 
What are you guys running for overall weight in the STM 60YS? I will have to add some as I think Allens spring is lighter then the one Im going with.

thnx
Dan
 
What are you guys running for overall weight in the STM YS? I will have to add some as I think Allens spring is lighter then the one Im going with.

thnx
Dan
I'm going to pull one out tomorrow and weight it, I'll get back to ya, maybe tonight if I get a chance.
 
8800 eh, I'd love to see a dyno sheet, not sure if Ben has released any.

The sled should make pretty much the same power from like 8400rpm to 9100ish on the dyno. Theres lots of dyno sheets out there. I think most clutch tuners reccomend tuning to around 9000 rpm in perfect conditions, that way in looser or heavier snow you are still in the peak power band. Alot easier to clutch one of these sleds than a 2 stroke with a peaky power band.
 
image.jpeg



image.jpeg


Ulmer spring on the left, stocker on the right.

80 grams, more weight than I thought.
 
What spring are they using in the primary and what' the engagement rpm ?
 
Not sure what exact spring it is, It's around a 30/90, engagement is similar to stock, if anything lower than stock but I can't remember. If I get a chance I'll fire up the sled and confirm.
 
ok I'll add a washer in the center and let you know what I get for rpm. One thing I can say is by adding the Powertrail flash my 137 now transfers weight and lifts the skis! haha want lift, simple just add 70-75hp
 


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