So I took both clutches off tonight.... and

Waterfoul

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Dec 13, 2004
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My primary, when you shake it, rattles like a baby toy! I'm pretty sure it shouldn't be doing that. I dropped them both off at SpartaSRX's house (he's home sick this week... bored... good for me!) and we both agree, all the rollers are absolutely shot. They flop all around just handling the clutch. So at a minimum I need new rollers and what ever goes with them (I don't know clutches, but I'm learning!). Maybe I'll get to ride this weekend yet!!
 

it will rattle if you shake it, because when it is not spinning the weights aren't in direct contact with the rollers, so when you shake it the weights will smack the rollers, making the noise. Make sure your rollers aren't loose and dont have excessive play, but they do need to be able to spin freely. Make sure the weights aren't gouged or grooved. Get a new primary spring if it is over a year or two old. Clean them real good with a scotch brite pad and hot soapy water, dry with compressed air. Get a new belt, clean that the same way as the clutches to get the mold off of it. Should get you up and running again like new.
 
Yeah, I know about the wieghts moving around, but you should see the rollers... they have a LOT of play in them... 1/8" in each direction. Way off what they should be. I'm sure Pat will look at eveything while he has it apart. I really want to get back out there! This cold I'm fighting might not let me though... I feel like crap again today...
 
Hey Waterfoul, that sled has what 4000+ miles on it and the clutch needs to be rebuilt ALREADY?!? LOL You'd better sell that piece before it costs you any more money!!! LOL (being sarcastic and only kidding, of course!)
Hebi
 
The yammie twins are hard on rollers & clutch weight bushings.The triples last for ever.
 
2-3-4 cyl

its because the 3 cylinder is easier on the crank from the 120 degree firing, basicly the 3rd cylinder cancels out the torsional vibration from the other 2 in lamens terms. This is also true on the new vector engines versus the rx1 engines, there was complaints about vector clutch chatter and the 3 cyl -4 stroke has the same problem as the 2 cyl -2 stroke does versus the rx1. The yamaha engineers said thay have fixed it by simply using a o-ring on the slider buttons to take up the extra clearance and to silence the pucks from the 3 cyl being a bit more torsional vibration.

You wanna see a engine thats hard on clutch's, the old wildcat 700 from cat used to eat them up like they were breakfast. Then again, they had the same idle quility as a harley davidson hog....lol
 
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yea i know about those wildcats eating up clutches, even my buddy's ZR 900 is nasty on clutches.
 
You gotta love Arctic Cat clutches. Even Cat tells you to rebuild them every 1500 miles.
Hebi
 
This was alluded to above, but every engine has a "torsional frequency". This is similar to what happens when you bang a tuning fork against your leg. If the "torsional frequency" point occurs at or near the peak power rpm, it can tear parts up at an alarming rate. This can be addressed by changing the total inertia of the spinning parts in the engine or primary clutch components, such that it moves the "torsional frequency" point away from the peak power rpm. This is often overlooked when changing clutch weights significantly, and can have disasterous results.
 
Ding said:
This was alluded to above, but every engine has a "torsional frequency". This is similar to what happens when you bang a tuning fork against your leg. If the "torsional frequency" point occurs at or near the peak power rpm, it can tear parts up at an alarming rate. This can be addressed by changing the total inertia of the spinning parts in the engine or primary clutch components, such that it moves the "torsional frequency" point away from the peak power rpm. This is often overlooked when changing clutch weights significantly, and can have disasterous results.

ya, but calculating a torsional frequency on a clutch kit is DEEP math.
 
Ding is absolutly correct, Frequency = SQT(K/M): K is the stiffness of a system and M is the mass. In an engine, the number of cyclinders and the spacing of the cylinders from each other in a rotational sence will determine vibration charictaristics of an engine. In a nutshell, everything has a natural frequency and the only way to change it is to either change mass (rotating inertia in an engines case or increase stiffness which is hard to do). Dampening is one way to accomplish dealing with what you have. Dampening will actually move the natural frequency farther from the critical frequency which is where things are most damaging. Many engine builders use a torsional mass dampner. There is a reason why BMW engines are so smooth. It is because they dampen out vibrations at a price over what say Ford does on there engines. Vibrations usually lead to durability but it is dependant on the sevarity and is not the only issue.

Da Fin
 


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