Primary springs

[AkSledHed]

Can someone tell me what the second number on the primary spring means? I was cleaning the clutches on the wifes sled and discovered that it was not the correct stock spring for her machine. She should have had a purple/green, 160/260 spring in it and instead it is a purple/pink 160/350 spring.

 

[Macattack]

First number is the engagement force and the second number is the finish force.

At 350 (verses anything less, like 260) you will need more flyweight mass and/or higher rpms to fully engage the primary clutch to full shift out. When you change to 260 you will need to either click down in numbers or loose some flyweight mass.

FYI, pay attention to your secondary and belt pinch. A change in primary spring may affect these as well.

 

[Crasher]

Pretty common for a spring change either by a prior owner or even a dealership. Depending on several factors like altitude, track, type of riding (trail or Mountains), gearing, driver size, secondary spring, fly weight, helix angle ect. and your particular style will determine your clutching needs.

I never leave my clutching stock, even on a new sled.

I use a 160-290 on an 05 REV 151 for my elevation. 160-320 works better if I go above 8,000 feet.

160-350 sounds kind of stiff but not knowing your sled or other factors, it may be just the ticket.

Dyno Joe's kit uses a pretty stiff spring for the primary and changes the secondary helix. Maybe someone did some clutch tuning to your sled that you are not aware of.

 

[AkSledHed]

Beings as its brand new I would think that the dealer would leave it as stock as possible. I can tell you this much, I do not ride above 4000 feet and ride mainly around the 500-2000 altitude range but I plan on hitting some hills a bit higher than that.

If this spring is too much for a basically stock sled then I need to change it, that's what i'm trying to find out.

I ride powder, mountains, and do some boondocking, very little trail riding if I can help it.

 

[SnowSnob]

If your in your target RPM range then leave it. More then likely there's some set screws in your pins. I run a 160/320 in the wifes 600 with hollow pins but we ride up to 8000'+
I'm going to install a 160/350 so she can run lower clicker numbers since the 160/320 had her running #4 or #5. Lower clicker numbers makes the motor pull harder, higher is more response but revvy.