Primary Clutch Bang

[NOS-PRO]

hblake20 - I play around with clutching a lot and have a few questions....

Does this happen while just trail riding?

Does it do it when braking hard?

Is your engine braking eliminated?

Is there a lot of belt residue on the clutches or surrounding area?

Does it back shift properly? (driving down the trail, letting off and then back on the gas)

By what you are telling me right now, I think the bushing is very tight and somewhat binding. This is happening when you let off the gas and the engine gets down to a low rpm....the clutch binds up, the weights don't have the rpm force to make the clutch return slowly hence making a slamming sound when it gets past it's binding point. This happens when bushings are new. I've seen clutches bind so bad that they wouldn't engage properly and have a very high engagement.

 

[sk-rx1]

I had what may be a related issue on my first day out. Was playing with the brake, seeing how had it was to operate the brake with one finger. I locked the brake and slid to a stop. When I let off the brake the motor did not come back to idle rpm, it would only run 800-900rpm, also very sluggish. I thought I had fouled a plug. I did not shut it off and rode back to the trailer. Shut it off and opened the trailer. When I restarted the sled to load it all was back to normal. Not sure what happened, I was however getting only 12mpg for the 1st ride, taking it easy.

 

[acadieman]

I had what may be a related issue on my first day out. Was playing with the brake, seeing how had it was to operate the brake with one finger. I locked the brake and slid to a stop. When I let off the brake the motor did not come back to idle rpm, it would only run 800-900rpm, also very sluggish. I thought I had fouled a plug. I did not shut it off and rode back to the trailer. Shut it off and opened the trailer. When I restarted the sled to load it all was back to normal. Not sure what happened, I was however getting only 12mpg for the 1st ride, taking it easy.

same thing appened to me last night the engine was running 800 to 900 rpm at a road crossing and when i let the trottle crossing the street it staled in the middle of the intersection an did not want to start right away... i was piss bad.. pulled it across the road and then turn the key off.. wait 1 min and try it agan and evrything was ok like it had reset , no more flashing light and no more allarm code... after that the engine seemed running stronger...i tried to reproduce it but was not able.... i called the dealer to explane this and he said i was the first one experiencing it... by the way its a 7000 cross country so i dont thing its clutch related...

 

[NOS-PRO]

acadieman - Sounds like TORS switch to me. Could it have got wet somehow?

Weird.....

acadieman - take a moment and fill in your location as per site rules. Just letting you know...thanks!

 

[acadieman]

acadieman - Sounds like TORS switch to me. Could it have got wet somehow?

Weird.....

acadieman - take a moment and fill in your location as per site rules. Just letting you know...thanks!

Ok but i don't know what is TORS switch (im french so...)

 

[Sled Dog]

Throttle
Over
Ride
Safety switch or TORS for short.

 

[jgustman]

So I made mention of this in another thread, but I think it warrants it's own discussion. I am coming off a Ski Doo so I am unaware of whether or not this is normal with Yamahas. Every time I let off the throttle on my viper the primary clutch slams back to disengage and makes a very loud bang almost like I am whacking it with a hammer. Is this a common trait of Yamaha clutches i.e. are they all like that or is this isolated to the clutches in our sleds. (Note: I am under the assumption that everyone's viper does this since some other members keyed in on the topic in the previous thread)

To further my question; first and foremost: should this be of concern? If so, are there ways to stop this from happening either from an adjustment standpoint or an aftermarket modification?

I believe when you notice it most is when you hit the brake quick, yes sometimes the driven clutch stops so quickly that the sheaves slam shut since the belt didn't have time to smoothly come out, happens quite often on my yamaha apex and old viper.... Oh, bet it only is happening at slower speeds like coming up to stop signs and quickly hitting the brake...right?