Team Secondary Failure

[shagsmc]

Just wondering if anyone has seen a failure like this. I do not imagine this is common so I am worried there is an other issue that caused it.

Its from a 2019 850 SKS 146.

Did not happen at WOT, was about 1/4. The belt start squealing 10 minutes into the ride. The belt was loose which was odd because I had just checked the deflection right before I left for the ride. I tighten it up and 2 minutes later this happened.

Polaris is going to warranty the sheaves and replace them, but I have to swap my helix and spring.

 

[damx]

Just happened to my buddy, on his 19 850 rmk. New clutch and belt warranty.

 

[Reg2view]

Likely a casting or metallurgy failure. Can't be that many miles. Assuming nothing unnatural, like a drop, loose parts run through it, belt explosion, etc., occurred previously. I would look at the primary very closely for anything that might have run through it.

 

[shagsmc]

I will be disassembling the primary. Thanks for the replys.

Just happened to my buddy, on his 19 850 rmk. New clutch and belt warranty.

Did he have excessive belt wear before the clutch failed?

 

[damx]

Nope not at all. But it destroyed the belt when it happened.

 

[shagsmc]

So took the secondary apart. It looks like there was a spot in the clutch at full shift that was letting the belt slip. This created heat, ate the aluminum. Any idea what could cause the belt to be slipping at this particular moment in the shift?

 

[BeartoothBaron]

Maybe it's been shifting too far out, I can't quite tell from those pics. The rubber marks and burnt spots are almost certainly from when it broke, so I'm looking more at the rest of the sheave. It's probably just a defective clutch, but would be a good idea to make sure it's not shifting too far out when you get a new one. Easiest way to do that is to run 3-4 lines down the sheaves with a sharpie and run it through it's paces. You want to see it wipe away most of the line; if it's wiping away the whole line, and especially if you see any marks on the hub of the secondary, then you have more problems.

 

[d8grandpa]

The centre to centre on your clutch’s may be off, same result as to short of belt.

 

[TRS]

I’m looking at this as an outsider. I’ve seen this with Yamaha clutches. The clutch melts away from water and belt heat. Looking at the secondary, at one point the primary took over and opened the secondary to full shift. Possibly the track was locked. The belt spin, along with moisture sawed the secondary and melted the aluminum. The evidence is not only on the stationary but moveable sheave.

 

[GreenState]

Just got my 2019 out of the shop for the same thing. The only light I can possibly shed on this, and it's purely speculation, is that I read on the FB 850 owner's group from a guy who had seen it before, was that a crank that was bent was causing wobble in the primary and causing the secondary to blow apart as we've seen.

Before mine went out, there was a LOT of vibration in the motor. Murph saw it. However, the primary got hit by a part of the secondary and got replaced at the same time. The vibration in my motor is now gone. Wondering if my primary that was apparently not well balanced from the factory was causing extra stress on the secondary.

 

[shagsmc]

Polaris has given me my new secondary, no questions asked was approved right away. I wanted the dealer to triple check alignment and such but they are backed up till almost the end of march, so I unfortunately am on my own with this if I want to keep ridding.

So the primary is making some odd noises. I have taken it apart and checked the rollers, weights and spring; everything seems good. No missing washer, no flat spots and no unusual rubbing. Here is a video of the noise the primary is making.

 

[Murph]

....I wanted the dealer to triple check alignment and such but they are backed up till almost the end of march, so I unfortunately am on my own with this if I want to keep ridding.

Contact TRS for one of his alignment bars. You can do the alignment at home.

where are you located?

 

[shagsmc]

Contact TRS for one of his alignment bars. You can do the alignment at home.

where are you located?

Northern Ontario, Canada.

I will be purchasing an alignment tool. Is there any validity in thinking the alignment is causing that 'knock'?

The centre to centre on your clutch’s may be off, same result as to short of belt.

If this was the case would I not see this in the belt deflection?

Wondering if my primary that was apparently not well balanced from the factory was causing extra stress on the secondary.

I also suspect something like this, unfortunately I doubt my dealer has the tooling to check if the primary is balanced. I'll have to contact a machine shop I imagine.

 

[Murph]

Buy the TRS alignment bar. The Polaris one lines up about .120” too far inward (can be seen by witness marks on the belt.) my motor was twisted and had way too much lead in. I installed a .125” shim on mag side rear mount and a .125” shim on PTO side front mount. My lead in is now 0.0” with TRS bar. My witness marks on belt are dead even.