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ok...ive heard a lot about clutch kits and weights and stuff..now WHAT DOES IT DO??? what does a clutch kit do?? what are weights for??? primary? secondary? what are weights?? and what happens if i change them???
 

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Discussion Starter #2
12 ppl read it and no body replied?? turns out im not the only person who doesnt know about it :D
 

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for a basic understanding of how the clutch system works you can look at something like this
http://travel.howstuffworks.com/snowmobile1.htm

understanding what is really happening when you change a bunch of things (springs, weights, helix) is much more complicated.

here's a more in depth look
http://www.snowtechmagazine.com/articles/2001/clutch/cltchtun.php
 

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Discussion Starter #4
ok what will a clutch kit do?? and how will it help me?
 

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it will make your sled accelerate faster. probably higher engagement. more aggressive helix angle and faster upshift and backshift.

upshift means how fast the ratio of the two clutches is changing as you accelerate. if you notice when you're on your sled, you pin it and the RPMs pretty much stay in one spot (high). the clutches are doing all the work shifting while keeping the motor in the peak power RPM range.

backshift is when you let off the throttle the clutches snap back to a better ratio for acceleration again, which is desirable for example when you slow down in a tight corner and then want to accelerate hard out of it.

this is all done by adjusting weights, springs and helix. stock clutch setups are made from the factory to be comfortable and somewhat tame. aftermarket companies put a lot of effort into keeping the motor in the peak RPM range all the time as opposed to having tame acceleration which makes the average rider more comfortable.
 

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Originally posted by Luke68Polaris
[br]12 ppl read it and no body replied?? turns out im not the only person who doesnt know about it :D
you should wait longer than 8 minutes to get some reply...[:D]
 

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Originally posted by Sleds-650
[br]I'm not a Math-ma-physicist, but correct me if I'm wrong. I believe there are infinite combinations of clutch weights/springs/helix/rollers...???
not exactly. there are optimum combinations to keep the RPMs in a specific area based on how much power is available and how much resistance there is from the drive train. you COULD theoretically make infinite combinations but it wouldn't function very well.

when it gets into the specifics of what combination will do what, for who. that's complicated. things can be calculated. but real world testing is where things are proven. it's too expensive for the average rider like us to keep buying and trying different combinations. the components add up quickly. so it's easier just to go with one of the aftermarket companies who have done the research and testing for you.

i personally don't know what will happen if you change things a specific way. i just know the basics and understand the overall mechanics of it. i personally can take guesses as to what happens when you change one component, but when a bunch of stuff is changed, it's beyond me.
 

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I'm no expert on clutches by any means, but I do know there are no stupid questions, just stupid mistakes. There are lots of knowledgeable people on here that will gladly answer any questions, or set you in the right direction, no matter how trivial they seem. Sometimes it may take a little while,but you'll get your answers.
 

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http://www.snowmobilefanatics.com/forum/topic.asp?TOPIC_ID=5566&SearchTerms=101,clutching
this will be helpful. i love these 101 posts they are lots easier to post than explain everything.
 

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Originally posted by Customized89Trail
[br]it will make your sled accelerate faster. probably higher engagement. more aggressive helix angle and faster upshift and backshift.

upshift means how fast the ratio of the two clutches is changing as you accelerate. if you notice when you're on your sled, you pin it and the RPMs pretty much stay in one spot (high). the clutches are doing all the work shifting while keeping the motor in the peak power RPM range.

backshift is when you let off the throttle the clutches snap back to a better ratio for acceleration again, which is desirable for example when you slow down in a tight corner and then want to accelerate hard out of it.

this is all done by adjusting weights, springs and helix. stock clutch setups are made from the factory to be comfortable and somewhat tame. aftermarket companies put a lot of effort into keeping the motor in the peak RPM range all the time as opposed to having tame acceleration which makes the average rider more comfortable.
Nicely said!!! Couldnt of done it better myself!
 

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Generally the goal of the clutching system is to send as much power to the track, while maintain the optimum RPM for power, while preventing over reving the motor.

The key to limitting the RPM of the motor with the clutches is to realize that the clutches are a load sensing setup. The secondary transmits the load from the track to the primary and based on that the motor determines how many RPM's it needs. At full shift out, the primary will be closed and the secondary will be open. With the primary fuller closed the load can't change anymore. The motor cannot increase RPM's because it sees a constant load.

Where do the weights come in. The weights are in the primary and are mounted on a pivot point. When the engine RPM's increase to engagment, the weights pivot out against the roller of the clutch by centripetal force. Now as the engine RPM continue to increase the weights continue to gain more force and overcome the pressure that the spring is applying. The spring holds the primary open under zero load conditions. So the spring is a key contributer to the where the sled engages and begins to move. However many people overlook the weights. As the weights get heavier they develop more force at a lower RPM. And as they get lighter they develop less force at the same RPM. So a heavier weight will engage faster than a lighter weight. Also a heavier weight will have a lower maximum RPM. Because it develops enough force to close the clutch completely at a lower RPM. A lighter weight will close the clutches later so they will develop more maximum RPM.

Just a note Ski-Doo uses weights and Ramps in there primary. I'm not well versed in their system.

Now how does the secondary work. The secondary is simple, it uses a ramp or a helix to open and close the clutch faces as the primary transfers power to it via the belt. The spring is there for one reason, to apply pressure to keep the clutch closed. But the main mover here is the helix. The helix has a certain measured angle or it can have several angles cut into it. The key to the secondary is to understand that it is purely load sensing. As the sled moves the track can encounter many loads, like travelling in powder or going uphill. Think about the system now, the primary closes making a larger diameter up front, and the belt has a very limitted amount it can stretch before it simply focres the secondary open. What happens when you hit those different load conditions is secondary does is it forces the belt back up the faces. So now the primary has now been openned slightly and now the ratio is changed between them to allow the motor to develop more RPM and more power to force through this high power situation. So by explaining that the helix is that load sensor, it determines the rate at which the faces open or close, determining how the ratio changes. A high angle helix will have a high rate of change and should respond to loads very fast. However there is a downside to that. One, is zero load conditions. This occurs when you let the sled coast, now a steep angle is tough for the clutch to come back to a good ratio. One reason why this occurs is because the spring creates more of a torsion action and pushes the suface of the clutch and the surface of the helix together and they bind. So this is why many sled companies have developped dual angle or tri-angle or even quad angle helixes. This changes that issue. No when the zero load condition occurs there is normally a smaller angle to travel on and now the spring assists more than fights this action. At low speed zero load condition the spring tensions isn't high enough to cause the binding so it will backshift well.

That's my understanding of the clutch system. Anybody feel free to make any corrections to my long winded response....
 

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clutch kits allow you to put the power to the track more efficently or quicker. Helps u play with with the clutch will engage, at a higher or lower RPM
 

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Originally posted by powder_special_900
[br]clutch kits allow you to put the power to the track more efficently or quicker. Helps u play with with the clutch will engage, at a higher or lower RPM
Yes but u must have some kind of traction like studs or 1.25 track. I found out that my sled was cluthed right just did not have the traction then this summer i bought a 1.25 ripsaw from erick and now i really found out what my sled's got.
 
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