Primary clutch exploded

[Thunder Products]

Are those Penetrant Test photos of the OPs clutch after this episode? Or just some random clutch that you discovered weakened?

Different clutch all together

This was noticed on a customers sled in for clutching service and clutch kit. Noticed the cracks where the weight pin goes thru and by the set screw. This was caught before coming apart....and still have the sheave here.

The penetrant test was done to verify the cracks were what we saw and to prove where the clutch starts to weaken.

 

[STAIN]

Many are switching back to the previous style primary (Viper, Nytro, Apex...etc.) with great results and zero issues

How are those replacing their clutches with the older style ones doing on belt wear/breaking? Any difference?

 

[ClutchMaster]

Pics from Penetrant test

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The old 2 stroke HH’s were shorter than the stock weights, I think that’s were the confusion stems from.
It would have been nice if the OP would have responded to whether he removed the roller after the failure.

 

[jonlafon1]

People need to understand that turning up the power/ putting more mustard on the dog is going to cause issues with clutches(if gone unchecked).. I know it goes without saying to some guys on here, BUT these clutches need to be looked at and checked every 500 miles or so. That is my rule of thumb and opinion. I replace my belt every year and just dropped new rollers in after 4500 miles.. The rollers were in good condition, but still replaced them.. Pull your clutches and break them down.. If your going to turn them up you gotta check for wear on everything in BOTH clutches.. CLEAN THEM.

Thanks Thunder for the HH post. As it seems some always want to blame certain products on this site. Thousands of miles on two different brand sleds with HH weights and have no complaints.. Surely other brand weights are great products on Sidewinders . Wonder what some would say if the poster had blown up using Daltons?

 

[ClutchMaster]

Actually I think the HH would be easier on the clutches, they use less weight to achieve the same forces. You would think the big heavy weights would be harder on the clutches.
The HH profile is an awsome race weight, used them on a lot of the 2 stroke machines with great success.
Maybe it’s an over tightening of the set screws causing failure?

 

[Fast]

Im on there all the time, still have not seen any. So please give link and not just speculation. I know about the warranty crack in 17, and PRE 17 TEAM issues, but if you go there now they are all mostly happy.

There are way way way more issues with YAM clutches, and belt life then TEAM period.

Dan

I was reading about team clutching a couple months ago on h/c sleds and there was a lot more issues than Yamaha not sure if they were boosted or not

 

[jonlafon1]

Actually I think the HH would be easier on the clutches, they use less weight to achieve the same forces. You would think the big heavy weights would be harder on the clutches.
The HH profile is an awsome race weight, used them on a lot of the 2 stroke machines with great success.
Maybe it’s an over tightening of the set screws causing failure?

Betting i run the HH weights lighter then 99 percent of sidewinders(tuned at 250ish) that are using heavy hitters. RUNNING 67.1 grams ... I still feel lighter weights and more helix angle(straight angle) is better. Lots of other factors of coarse(springs) But the weights that are actually lighter BUT "act" heavier IMO better

 

[ClutchMaster]

Betting i run the HH weights lighter then 99 percent of sidewinders(tuned at 250ish) that are using heavy hitters.. I still feel lighter weights and more helix angle(straight angle) is better. Lots of other factors of coarse(springs) But the weights that are actually lighter BUT "act" heavier IMO better

Nice cooool clutches too I bet!
They remind me of 8bu-00’s, fastest weights for an SRX period. (Just ask Tony 3:16) he’s probably in an old folks home by now.

 

[jonlafon1]

Nice cooool clutches too I bet!
They remind me of 8bu-00’s, fastest weights for an SRX period. (Just ask Tony 3:16) he’s probably in an old folks home by now.

Yes I tried to get them hot. I posted. Ran it for several miles up over a hundo> stopped could grab and hold clutches anywhere. the belt was warmest of the three if i remember correctly. I also remember hearing the boiling sound after I shut it down after the long pull. thinking damn I should have ran it further to cool it down some but wanted to feel clutches immediately after long pull.

 

[Mototown]

Actually I think the HH would be easier on the clutches, they use less weight to achieve the same forces. You would think the big heavy weights would be harder on the clutches.
The HH profile is an awsome race weight, used them on a lot of the 2 stroke machines with great success.
Maybe it’s an over tightening of the set screws causing failure?

The curvature on the weights on the heavy hitters multiplys the force on the rollers .... reason for less weight, but the force on the rollers will be the same or more ( and probably how they are getting 16 mph gains on there skidoo 850 kits lol ) . And the reason for less failures with some weights ....

 

[KnappAttack]

The old 2 stroke HH’s were shorter than the stock weights, I think that’s were the confusion stems from.
It would have been nice if the OP would have responded to whether he removed the roller after the failure.

This is possible, I have a set off HH kicking around here from an old turbo RX-1 though and they too are shorter. It's quite easy to see, or maybe I should say were shorter than all the others. Not to say they haven't changed them over the years. I'll dig around and see if I can't find them somewhere.

The part that gets me is every picture THAT I HAVE seen of broken or blown Winder clutches, has had HH's in them when they have let go, haven't seen any other pictures of blown clutches mentioned anywhere else with stock or any other brand of weights. It's always the HH weight, just what I have noticed in all these pictures, so is it too much dead weight on the heel and pivot point just over stresing the pivot? Could it be the weighs are breaking at the threads and then blowing out? I've seen pics that show these weights broken at the threads, but which came first, the broken arm or the broken clutch?

If theres other clutches out there with something different in them for arms, then I'd like to see the postings or pictures of stock or other weights along with that blown clutch. There must be some links to all these blown clutches that are out there. From the sounds of it there must be a rash of them coming apart. Weird part is this being the go to Yamaha site, I've only seen talk and pictures of a select few. And everyone of them had the same weight design in it. I'd be pizzed if it was my clutch exploding because it wasn't strong enough and posting plenty of pics to warn others of the impending doom so it wouldn't happen to them.

My clutch eats rollers for breakfast and rattles like a SOB at idle and 35-50 MPH or so, same as my 1200 did with the rattling bucket of bolts TRA. Hence the reason to try the Team Primary and the PB80 at some point.

 

[NYTurbo]

We had a clutch with STMs let go on the weekend. Roller was still intact and little to no play. Yesterday we pulled belt and spring out of another clutch with STMs and they shouldn't come out by the roller. We also eye balled the STMs and stock weight on a clutch pin with weights side by side and they are very very close to the same length.

This one blew at full throttle , and the belt blew as well, which happened first were not sure. Seems to be a lot of these starting to fly apart. Someone is going to get hurt, these weights have a lot of momentum and are heavy enough to do some damage.

 

[Doowithblue]

Anyone who runs over 80grams in a stock winder primary is asking for trouble imo. Maybe even 78g. Clutch isn't made for that kind of power. Tapp or stm for big power. I'm betting over 9000rpms isn't doing it any favours either.

 

[Thunder Products]

This is possible, I have a set off HH kicking around here from an old turbo RX-1 though and they too are shorter. It's quite easy to see, or maybe I should say were shorter than all the others. Not to say they haven't changed them over the years. I'll dig around and see if I can't find them somewhere.

The part that gets me is every picture THAT I HAVE seen of broken or blown Winder clutches, has had HH's in them when they have let go, haven't seen any other pictures of blown clutches mentioned anywhere else with stock or any other brand of weights. It's always the HH weight, just what I have noticed in all these pictures, so is it too much dead weight on the heel and pivot point just over stresing the pivot? Could it be the weighs are breaking at the threads and then blowing out? I've seen pics that show these weights broken at the threads, but which came first, the broken arm or the broken clutch?

If theres other clutches out there with something different in them for arms, then I'd like to see the postings or pictures of stock or other weights along with that blown clutch. There must be some links to all these blown clutches that are out there. From the sounds of it there must be a rash of them coming apart. Weird part is this being the go to Yamaha site, I've only seen talk and pictures of a select few. And everyone of them had the same weight design in it. I'd be pizzed if it was my clutch exploding because it wasn't strong enough and posting plenty of pics to warn others of the impending doom so it wouldn't happen to them.

My clutch eats rollers for breakfast and rattles like a SOB at idle and 35-50 MPH or so, same as my 1200 did with the rattling bucket of bolts TRA. Hence the reason to try the Team Primary and the PB80 at some point.

We, at Thunder Products Clutching are gathering info from all over Europe and North America and continuing to monitor the status of these clutching issues. We are watching all of social media and forums, plus gathering information from our dealers on what is happening with this Sidewinder Primary clutch.

The 48 gram HH weights that we sell for the older 2 stroke sleds are the same length as the 58 gram weight and the 74 gram weight that I have included pictures. These weights haven't been changed in years and have plenty of weights here that we checked all of our inventory when this issue about weights being too short came about. All I can say is our HH weights are not shorter than the original Sidewinder weight and definitely longer than other weights.

There have been clutches coming apart with ALL weights....even stock. The clutch sheave pictured in my previous post with the cracks was from a stock clutched, stock flashed sled.

If there are any clutch cracking or coming apart problems....PLEASE bring this up to the attention of your dealer! This clutch is defintely not strong enough to handle the power of these turbo sleds.....even stock

 

[ClutchMaster]

The 48 gram HH weights that we sell for the older 2 stroke sleds are the same length as the 58 gram weight and the 74 gram weight that I have included pictures. These weights haven't been changed in years and have plenty of weights here that we checked all of our inventory when this issue about weights being too short came about. All I can say is our HH weights are not shorter than the original Sidewinder weight and definitely longer than other weights.

There have been clutches coming apart with ALL weights....even stock. The clutch sheave pictured in my previous post with the cracks was from a stock clutched, stock flashed sled.

If there are any clutch cracking or coming apart problems....PLEASE bring this up to the attention of your dealer! This clutch is defintely not strong enough to handle the power of these turbo sleds.....even stock


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I personally don’t think it has anything to do with the weights OK.
I stand corrected about the length, my confusion stems from using you weights years ago and seeing them right on the edge of the rollers. I thought they were shorter but they could have been ground down now that I think about it.
I’m definitely losing my mind with age sorry for the confusion.

Still not ruling out that worn rollers can cause this failure tho.

Many of you on the site do frequent maintenance, this is not the case with your “Average snowmobiler” I’m sure many don’t even know what a clutch roller is and drive thousands of miles without even looking at them.