Primary clutch exploded

[Thunder Products]

Would this be cause by over torquing

Could be caused by over-torquing....which is an assembly issue from the manufacturer...which is why this guy Tommy is going to bring it in to his dealer.

WTF is going on? That is not good. Really would like to know what’s causing this? Harmonics? Over torqued set screws? What’s crazy is it’s stock ones not just boosted up ones. That’s really low miles. Any indicators from the owner of this clutch in the picture?

The owner is pissed, but glad it was noticed. Tommy's sled is 100% stock. He rides trail and the history of the sled is 2 blown belts in 1,486 miles. Wanted to try a clutch kit and wanted us to check his offset to correct his belt issues. His sled is also going in for the dreaded oil leak that is between the oil tank and the chain case cover.

Would be nice to get a better picture of the cracks Terry just so we know what and where to look. Awesome you caught it before failure. Scary.

This picture is the bottom one from above post from Tommy's stock sled and the pic I posted long ago when this started happening with Dye Penetrant. The crack clearly shows going in a 90° straight thru to the allen screw and straight up the casting. And yes, they are cracks that will eventually lead to some unlucky person which happened in the 3rd pic.

What's not good? I don't see any cracks.

I don't see any cracks there. Dirty, but no cracks I can see there.

The cracks are there and wish more members would be more supportive about this issue as these clutches are coming apart and will definitely hurt someone. We see 2-3 a week on social media and get calls about options on what to do to replace the clutch. These are definitely cracks which I have proved over and over with pics, information and dye penetrant testing... and have contacted Yamaha directly numerous times. Our clutch repair facility in Sault St. Marie has had numerous clutch issues show up. They work on every brand of sled and the TEAM primary along with the SW clutch numbers are beginning to be a huge problem.

 

[cannondale27]

Could be caused by over-torquing....which is an assembly issue from the manufacturer...which is why this guy Tommy is going to bring it in to his dealer.




The owner is pissed, but glad it was noticed. Tommy's sled is 100% stock. He rides trail and the history of the sled is 2 blown belts in 1,486 miles. Wanted to try a clutch kit and wanted us to check his offset to correct his belt issues. His sled is also going in for the dreaded oil leak that is between the oil tank and the chain case cover.




This picture is the bottom one from above post from Tommy's stock sled and the pic I posted long ago when this started happening with Dye Penetrant. The crack clearly shows going in a 90° straight thru to the allen screw and straight up the casting. And yes, they are cracks that will eventually lead to some unlucky person which happened in the 3rd pic.
View attachment 146564 View attachment 146565 View attachment 146567






The cracks are there and wish more members would be more supportive about this issue as these clutches are coming apart and will definitely hurt someone. We see 2-3 a week on social media and get calls about options on what to do to replace the clutch. These are definitely cracks which I have proved over and over with pics, information and dye penetrant testing... and have contacted Yamaha directly numerous times. Our clutch repair facility in Sault St. Marie has had numerous clutch issues show up. They work on every brand of sled and the TEAM primary along with the SW clutch numbers are beginning to be a huge problem.

I agree. Glad you are documenting. That first pic in above post is the one I can’t see anything cracked leading to set screw. Just something going 90deg to it.

 

[Wingwong]

Could be caused by over-torquing....which is an assembly issue from the manufacturer...which is why this guy Tommy is going to bring it in to his dealer.




The owner is pissed, but glad it was noticed. Tommy's sled is 100% stock. He rides trail and the history of the sled is 2 blown belts in 1,486 miles. Wanted to try a clutch kit and wanted us to check his offset to correct his belt issues. His sled is also going in for the dreaded oil leak that is between the oil tank and the chain case cover.




This picture is the bottom one from above post from Tommy's stock sled and the pic I posted long ago when this started happening with Dye Penetrant. The crack clearly shows going in a 90° straight thru to the allen screw and straight up the casting. And yes, they are cracks that will eventually lead to some unlucky person which happened in the 3rd pic.
View attachment 146564 View attachment 146565 View attachment 146567






The cracks are there and wish more members would be more supportive about this issue as these clutches are coming apart and will definitely hurt someone. We see 2-3 a week on social media and get calls about options on what to do to replace the clutch. These are definitely cracks which I have proved over and over with pics, information and dye penetrant testing... and have contacted Yamaha directly numerous times. Our clutch repair facility in Sault St. Marie has had numerous clutch issues show up. They work on every brand of sled and the TEAM primary along with the SW clutch numbers are beginning to be a huge problem.

Thanks for your hard work

 

[Keith Schmitz]

Guys, i did start a Pro4 clutch review earlier in the year. I don’t know what exactly breaks the primaries, but regardless, I’m having nothing but good luck with the Pro4. We spend all this money on these things to go faster and faster, so, i bought as an insurance policy. Should the stock primaries be blowing up/grenading? Absolutely not. Just saying there are options out there that work.

 

[Crossfire12]

Guys, i did start a Pro4 clutch review earlier in the year. I don’t know what exactly breaks the primaries, but regardless, I’m having nothing but good luck with the Pro4. We spend all this money on these things to go faster and faster, so, i bought as an insurance policy. Should the stock primaries be blowing up/grenading? Absolutely not. Just saying there are options out there that work.

I want one but how will they last being that there untested, being new? I know TAPP is good they been out for a long time, I don’t like the tap setup because I just like the old time weights that we been using for years, Simple. TAPP is like skidoo clutch. I will replace my primary by next season. I can’t see the pro4 breaking in that area.

 

[ROCKERDAN]

I want one but how will they last being that there untested, being new? I know TAPP is good they been out for a long time, I don’t like the tap setup because I just like the old time weights that we been using for years, Simple. TAPP is like skidoo clutch. I will replace my primary by next season. I can’t see the pro4 breaking in that area.

TAPP would be my choice....But my stock YAM primary looks mint still(touch wood). Maybe its something with other weight bushing wearing or rollers going out, or belt blows....who knows.

I like the TRA style system better, with clickers for quick rpm changes. 10k mile first inspection is quite stunning.

Dan

 

[Keith Schmitz]

TAPP would be my choice....But my stock YAM primary looks mint still(touch wood). Maybe its something with other weight bushing wearing or rollers going out, or belt blows....who knows.

I like the TRA style system better, with clickers for quick rpm changes. 10k mile first inspection is quite stunning.

Dan

It’s just a preference, and what i went with. Different strokes for different folks

 

[Thunder Products]

@Keith Schmitz

You have quite a few miles on your Pro-4 already...

I like how easy it is to adjust weights

 

[Thunder Products]

Thanks for your hard work

Thank you

 

[Keith Schmitz]

I kind of equate this clutch situation to construction. I’m an iron worker by trade. If you’re making a pick with a crane, that weighs, let’s say 10k pounds. Even with the SWL (Safe working load which i believe is 5% less than max load) you wouldn’t grab a 3 ton shackle to make the pick. You’d grab a 5T.

The MAJORITY of the clutches that are exploding are on tuned sleds. In some cases, we are adding 15-20 % more power than these clutches were designed for.

So is a shotty design? Yes. Should YAMAHA be aware & try to remedy the problem? YES!

We need to take some responsibility also...IMO

 

[Crossfire12]

Guess we’re gonna have to cut back on the power, say 170 would be safe! Think about it from stock 200 to 300hp that’s a hell f a jump without modifying.

 

[STAIN]

TAPP would be my choice....But my stock YAM primary looks mint still(touch wood). Maybe its something with other weight bushing wearing or rollers going out, or belt blows....who knows.

I like the TRA style system better, with clickers for quick rpm changes. 10k mile first inspection is quite stunning.

Dan

I will find out, just broke open the piggy bank.....

 

[KnappAttack]

Put your glasses or buy a bigger Ipad

Nope, Still see no cracks.

 

[fatchance]

The casting flash is a bit ugly and concerning, but it's held together running the 300 tune. I bought a back up when i thought i saw a crack under the set screw, but after hitting it with some ScotchBrite it didn't look nearly as bad.

 

[Thunder Products]

Guess we just go switch over to the TEAM clutches....cause I don't see any cracks on these
(FYI Won't be switching to the TEAM clutch anytime soon.)

a bunch of different sleds with TEAM clutches

Next sled

1 more

Next Sled

Next sled

Waiting for the dealer and/or Tommy to get back to me as we offered to do the dye penetrant testing on it to prove to Yamaha even more on this issue.