Spring Question

[Stone9]

I am running the 14.5 mm rollers and a helix from a Viper. I am also running the stock Nytro spring (Blue). Should I find a pink spring? What have others running this set up found?

 

[Schlick55]

It all depends on what cut the Helix is. I just installed the 14.5 rollers and a Blue Pink Blue spring and it brought the engagement down to about 3050. What is the part number on the Helix? I assume you don't have any snow down by Cherokee, so far this winters sucks!!!

 

[Stone9]

It is the stock 47 degree helix from a viper. I did this setup last year because of Turks recommendation. It lowered engagement to about 3250 to 3350 but after just 2 WOT runs I had alot of heat coming of the clutches. Not burning hot but just enough to piss a guy off. I am not using any shims. Would shims lower it further? Also is the pink spring softer or harder than the blue?

 

[Stone9]

Ok I found the answer to my question. Blue Pink BLue is a soft spring which will lower engagement but it will also lower top end rpm's. What is your rpms running. As of now mine is at about 8950 which is just about to the sweet spot.

 

[dburrowes]

Totally off topic but great Profile Pic Stone.

BTW - You guys there are complaining.......my grass is still mid summer green...not impressed. Thats OK - Start late....End late.

 

[UP bushman]

Rule of thumb on primary springs is Preload affects engagement and Spring Rate affects rpm shift out. A lower Preload decreases engagement rpm and higher Preload increases engagement rpm. A lower Spring Rate will decrease shift out rpm while a higher Spring Rate will increase shift out rpm. The primary goal should be a straight shift out meaning if your peak power is 8950 rpm at take off to top end you want the shift out to be as close to 8950 all the way through WOT.

Examples you can change engagement with the primary weights also. More weight in the tip raises engagement rpm while weight towards the heel lowers engagement rpm. Blue Pink Blue has a Preload of 30Kg and Spring Rate of 2Kg. If you are experiencing lower shift out rpm than peak 8950 rpm at WOT say 8500 rpm. You can use a spring color of White Pink White with Preload of 30Kg to keep engagement rpm the same and Spring Rate of 2.25Kg to raise shift out rpm. Always tons of variables in clutching and many ways to get there.

 

[Stone9]

Dburrowes...Thanks man. I looked tonight and My fathers 08 rtx nytro has all stock clutching as far as I now but I believe he has a yellow silver yellow spring in his prime. His engagement is at 3600 and Top rpm is 9000. his sled can keep the skis off the ground about a foot for as long as I can hold it WOT in any snow conditions. I wish my sled would do that