Clutch Springs ???

[99summitx]

Ok i know nothing about clutching so I go to the peeps of S&M. Springs, what do the lbs on spring mean and do. For example my stock primary clutch spring is Purple/yellow 160-260. So I guess i'm asking what would a 160-320 do compared to stock?? Need the physics of this thanks

 

[Summitric]

ok i know nothing about clutching so i go to the peeps of s&m. Springs, what do the lbs on spring mean and do. For example my stock primary clutch spring is purple/yellow 160-260. So i guess i'm asking what would a 160-320 do compared to stock?? Need the physics of this thanks

if you're ever in edmonton, i have a ski-doo "racing manual" given to me by another member, and it explains the spring pressures and lists all the different rates of the springs in it.......... The purple/yellow is just the part identifier as there are all different color springs with different pressures and collapse rates..... The 160/260 is the way they measure the pressure put on the springs..... I think i have an all white spring in my '99?? Can't remember now(getting old).

 

[maxwell]

When it comes to springs and their forces, I always hear or read the word "Rate" when the word "force" should be used. Here people describe a quantity of a spring and are not referring right to the element of the spring.
Rate is the fixed ratio between two things. In the case of a spring, rate is the quantity lbs measured per inch of change. You compress the spring it takes "x" amount lbs of force (per inch) to change the height of the spring. The starting point is the installed height and the finish point is the full compressed height. The installed height is at rest or the engagement or beginning of the shift. The full compressed height. is at full shift.
Force is the strength or energy exerted or brought to bear to hold something in position. For example a 170-300 primary spring. The spring needs 170 lbs of force to keep it at installed height and must add enough force of up to 300 lbs to change it's position to full compressed height..
***The spring does not have 170 lbs "rate" at the beginning of the shift.
The spring at installation is compressed 1.25" and requires 170 lbs of force to keep it that position.
The spring at full shift is compressed to 2.5" and requires 300 lbs of force to keep it that position.
To figure out the rate of the spring you do a simple calculation.
i]300 lbs - 170 lbs = 130 lbs
ii]2.5" - 1.25" = 1.25" of distance travel between engagement and full shift.
130 lbs / 1.25" distance = 104 lbs/inch of rate.
From installation height of 1.25" then you want to compress it just 1" more, you would have to add another 104 lbs on top of the 170 lbs to make the spring compressed to 2.25". To keep the spring compressed at 2.25" that would mean you did 170 + 104 = 274 lbs to keep it in that position.


Getting back to my pet peeve about "force" and "rate" example:
Q]...Change to a softer spring, one with less finish rate in the primary. Softer primary spring has faster up shift.
A]...For fun to talk of the 170-300 spring, the idea given here is to lose the 300 and go with something lower. For lack of better numbers lets say "260".
Might want to change to a 170-260 from a 170-300.
Now that you know the definition of rate, what do you think when you read this quote where the word "rate" is used? Right idea, however not using the correct term. I'd like to correct the Q] by having the word rate exchanged with "force".
New Q]...Change to a softer spring, one with less finish "force" in the primary. Softer primary spring has faster up shift.



Clutching IQ - Northern Catalyst Performance Clutching Systems

 

[Summitric]

Ouch, don't be peeved at me... I never mentioned the word rate, but i used "pressure", which is similar to force(actually in automotive terminology, pressure would be more applicable to this)...... Good information though

 

[maxwell]

Ouch, don't be peeved at me... I never mentioned the word rate, but i used "pressure", which is similar to force(actually in automotive terminology, pressure would be more applicable to this)...... Good information though

lol no thats straight from DJ ahahaha i couldnt come up with that

 

[Modman]

....Change to a softer spring, one with less finish rate in the primary. Softer primary spring has faster up shift.
A]...For fun to talk of the 170-300 spring, the idea given here is to lose the 300 and go with something lower. For lack of better numbers lets say "260".
Might want to change to a 170-260 from a 170-300.
Now that you know the definition of rate, what do you think when you read this quote where the word "rate" is used? Right idea, however not using the correct term. I'd like to correct the Q] by having the word rate exchanged with "force".
New Q]...Change to a softer spring, one with less finish "force" in the primary. Softer primary spring has faster up shift.

Great info in the above post. I do want to point out though that this is the assumption that the weights are staying the same. Softer spring does not necessarily equate to a faster upshift if the weights are adjusted accordingly. That's the beauty of the CVT, so many infinite combinations to help adjust. Also, with all springs, wire diameter and # of coils will determine the spring force, and typically, there is a compromise between the final # and the engagement # which means that other components can be changed to adjust the engagement RPM and final shift points as well.

 

[99summitx]

Great info in the above post. I do want to point out though that this is the assumption that the weights are staying the same. Softer spring does not necessarily equate to a faster upshift if the weights are adjusted accordingly. That's the beauty of the CVT, so many infinite combinations to help adjust. Also, with all springs, wire diameter and # of coils will determine the spring force, and typically, there is a compromise between the final # and the engagement # which means that other components can be changed to adjust the engagement RPM and final shift points as well.

"so many infinite combinations " that's the whole problem...where to start.

 

[Modman]

"so many infinite combinations " that's the whole problem...where to start.

PM me with what you are looking for and what type of riding you do. I might have a spring that you can try, I have a "few" extras for the TRA clutches. I recommend an adjustable pin kit for any TRA, adding weight on the tip is a big help to that clutch and you can change them on the hill without a ton of tools. You can add to your pin kit by getting more set screws from the local hardware store as well, making it more versatile than how you bought it.

I got mine from Recreation Supply in Sask, but you can get them from Goodwin Performance and The Crankshop as well.