Ulmer clutch kit question

[Mills]

Just installed the Stage 2 Ulmer Racing clutch kit I bought at Haydays for my '08 Nytro. The new spring that comes in the kit for the primary was about 0.25" shorter than the stock primary spring. I tried to contact Ulmer but they are extremely busy and unable to answer the phone so I thought I would ask here. Is the Ulmer primary spring supposed to be shorter than the stock primary spring? If so, why? I would assume it is to help with the "launching" of the sled at engagement.
See pic of the Ulmer (on left) and stock spring (on right).

 

[Big_Phil]

Its fine, the ulmer spring is a yamaha spring.

Ive never measured mine, but I have that same orange pink orange spring. I couldnt tell you why its shorter, but I know it works.

 

[Mills]

Did several test hits tonighy and it works great.

 

[MrSled]

Did several test hits tonighy and it works great.

I told you it would be fine...

 

[nytrozula]

If you go to the TotallYamaha.com side you will find a link to "technical pages". In there go to snowmobile tech, clutches and jetting, then clutch components. Here it describes the different springs and their characteristics.

 

[MrSled]

or click on the TY Tech in the menu above... here is the short cut. http://www.totallyamaha.com/snowmobiles/aaTECH/TechIndex/clutches.html

Scroll down..

 

[Mills]

That explains it well thanks guys. Ran the sled last night. Just need to add a bit more twist angle to the secondary for better back shift. This kit definitely improved the "launch" problem Nytro's have at initial engagement and when accelerating out of a corner. It was well worth thr money.