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Discussion Starter · #1 ·
that is, I'd like it explained. I have a good basic understanding of how clutches work. Though I don't understand how you can get make your sled that much faster just by clutching. I realize by adjusting the clutches that you can change the RPM that the clutch engages at, and how "hard it hits".

I can't say I've ever really sat down and stared at my sled clutches. Why is there a need for two clutches? Why is the stock setup so crappy?

When I'm going along at say 30mph in my 570, when I giver some gas, the track spins, (obviously I can control this by how much gas I give it) I don't see how clutching can make the sled any faster if I already have the ability to spin the track.

Any input welcome :)
 

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I am Spartacus
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Clutching controls the RPM where it takes off, as well as what RPM range it runs in wide open, right? Gearing really makes it faster more than clutching does. I'm interested in this topic also. Anyone?
 

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four gear pinned
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the stock gearing and clutching on sled are just about as good as you are going to get.( at least on the race sleds) we do speed checks of 150 feet, and with the stock springs and gears I hit about 48 mph. I gained 1mph by putting a red/blue team spring/ that is about it.


secondary operation.

the spring have alot to do with were the belt is on the clutch sheaf. it there is a weaker spring the belt will suck down farther into the sheafs, thus giving a bigger top end speed, but this looses throttle response. on the race sleds there is a stiff spring on the back this gives a better low end. the helix controls how the sheifs seperate as the belt senses pressure form the track this is what the secondary is on the sled for. it compensates for the track not moving as fast as the rest of the sled.

primary operation.

it is kinda the same, the primary must be spun at a certin rpm to ingage it. a stiff spring=higher rpm ingagement. this also controls were the belt is on the clutches. the weights are used to colaspe the spring and force the sheafs to grab the belt.
 

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Discussion Starter · #4 ·
but at a certain RPM, everything is "locked up" right, like nothing is slipping is anywhere, so how can springs determine top speed? because at that rpm everything is locked up :confused:
 

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springs do control speed, if you put in a high ingagement primary there will be less top speed= you run out of engine, the belt also stays higher in the clutch. which makes it kinda like gearing, the higher the belt stays in the clutch the lower the speed but more power at the start and from like 0-50. the secondary is for when the track catches up with the motor. the stepper the helix the faster the shift snox helixes have a very steep angles, this keeps the belt high in the sheifs.

I dont know what you mean by locked up?
 

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Discussion Starter · #6 ·
belts are so confusing....I like chains :D

locked up, as in ZERO slip, the engine/primary is moving the same speed, and the secondary is moving the same speed as the primary (factoring in gear ratio)
 

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no they never stay in one spot for a long time, I mean if you hold the throttle at the same rpm and go straight down the lake with no bumps to cause the track to leave the ground. then it might. under regular conditions the the secondary will seperate when you let of the throttle. they are even coming out with a lower gear that has a slip clutch in it to prvent the chain from breaking when you land a jump on the pipe. the new ski doo race sled has that b/c they broke so many chains last year.
 

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When changing primary springs, you increase the engage point, where the sled starts to move, when you do that, the initial "hit" or amount of power the machine sends through the drive train. I like a higher hit rpm, more of a "snap" from the get go.

check this out.

Clutching Explained
 

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smallengineguy said:
So, the helix does what?
the helix controls the speed that the secondary opens and closes, the two sheeves slide on the angles of the helix. Thus the spring stiffness controls velocity of opening/closing and the angle also controls tho....

if you've ever had the secondary open to change a belt the sheeves had to ride the angle of the helix to open, thats why the sheeves slid in a circular motion as opposed to pushing apart
 

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four gear pinned
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well I hope that cleared up evey question you have.
 

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I am Spartacus
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All set. Always wanted to mess with the clutching on my sled, but I might keep it like it is now. Bone stock, but lifts the skis a foot when you get on it. Why mess with that??? ;)
 

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Trust me, CHANGE IT! GEt a better Helix! They help DRAMITCALLY IN AGRESSIVE TRAIL RIDING! It gives it the "pep" and "torque" you wish it would have!
 

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springs will help alot if your sled is not were you want it. however if seg likes were his sled is now dont change a thing. gears wont help much either.
 

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Great discussion...

Learned a lot!
 

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sesnopro said:
well I hope that cleared up evey question you have.


Almost.......:D




On older sleds there is the phenomena known as "shifting out" when you feel like it shifts into a higher gear. It's a very smooth thing not unlike a car with a bad auto trans slipping into high drive or overdrive.

My Yamaha 86 enticer 340 is very noticeable as was my 74 GPX433.

So, what causes this and is it affected by helix spring changes?




Ryp
 

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Ryp said:
Almost.......:D




On older sleds there is the phenomena known as "shifting out" when you feel like it shifts into a higher gear. It's a very smooth thing not unlike a car with a bad auto trans slipping into high drive or overdrive.

My Yamaha 86 enticer 340 is very noticeable as was my 74 GPX433.

So, what causes this and is it affected by helix spring changes?




Ryp
maybe your buttons(what the helix slides on) were worn out or maybe your helix was just deformed in some way causing a rough shift out....but who knows for sure. Take it apart and look at all the parts
 
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