Clutch Taper change? Clutch wont fit crank. Help

[Golanda]

I replaced the crank shaft on my 2020 800 AXYS now my clutch won't fit. It fits on the old crank. I looks like I have a 2018 crank and a 2020 clutch.

I'm hearing that Polaris change the clutch taper in 2019, IDN.

Can the clutch be machined to the old taper?

Will a 2018 clutch just bolt up to the 2018 crank and work as is?

Other options?

 

[gtwitch]

Go see Sandy or call TRS in Cody
gtwitch in wyoming

 

[Golanda]

Learned a few things.

The 2020 AXYS 800 has the same crank as the 850. That means it has the same increase taper where the clutch engages. I'll have to get a 16-19 clutch to fit the 2019 crank I installed.

I also learned that in 2020 Polaris changed the PTO bearing, The new design allows the crank flywheel to walk on the pin until it contact the case wall and siezes up. That is the cause for my original sled failure. Polaris changed the design (2022 ish) to incorporate a locating ring in the bearing and crank case to keep things from moving along the crank.

For more on the crank/bearing go to -

Redesigned 850 Crankshaft

In development for 3 years, Indy Specialty has designed and is now manufacturing a full Billet 850 Crankshaft. This crankshaft was designed with one Major thought in mind...... ( dependable ) High Mileage The most significant change is in the PTO - end ..... which can be used to replace the...

www.snowest.com

 

[madmax]

You’ll need a new clutch. I believe if you installed an 18’ crank into your 20’ engine the output shaft on the 18’ is smaller than your 20’ clutch.

 

[BeartoothBaron]

Learned a few things.

The 2020 AXYS 800 has the same crank as the 850. That means it has the same increase taper where the clutch engages. I'll have to get a 16-19 clutch to fit the 2019 crank I installed.

I also learned that in 2020 Polaris changed the PTO bearing, The new design allows the crank flywheel to walk on the pin until it contact the case wall and siezes up. That is the cause for my original sled failure. Polaris changed the design (2022 ish) to incorporate a locating ring in the bearing and crank case to keep things from moving along the crank.

For more on the crank/bearing go to -

Redesigned 850 Crankshaft

In development for 3 years, Indy Specialty has designed and is now manufacturing a full Billet 850 Crankshaft. This crankshaft was designed with one Major thought in mind...... ( dependable ) High Mileage The most significant change is in the PTO - end ..... which can be used to replace the...

www.snowest.com

Interesting. I wonder if they went back to MAPE for the 800 crank in '20? Part numbers are different for 20 vs 19 (makes sense with the clutch taper), but I can't find any interchange with the 850. The 800 definitely kept the same type of PTO bearing. The Fuji cranks started in '13, and my understanding was that the 800s stuck with Fuji to the end; not so sure on the second part. I can't find positive confirmation on the 850, but what's stuck in my mind is that it had MAPE crankshafts from the beginning. Anyway, if the '20 has a MAPE crankshaft, then you're making an upgrade going to the earlier crank. Sucks about the clutch though; I'd think you could machine from the smaller to the bigger taper, but not the other way. More of a hassle than a show-stopper (unless you're in a rush) though. Even if you could machine your clutch, it might be quicker and cheaper to sell the core and buy an earlier one.

 

[Golanda]

Yes the output shaft on the 18 that I installed is small than the 20 that was on it.. I purchased a 18 clutch and it fits. I'm waiting on a clutch alignment gauge to assure everything lines up.

It appears I got lucky not repairing or replacing the 2020 crank.

 

[Massif master]

The 2019 850's PTO crank bearing would walk but in 2020 Polaris installed a locking ring to correct the problem and that applies to the RMK 800 2020 as well, so the crankshaft should last...good luck!