7800mi Service 16 Jackshaft upgrade and Driver/Shaft change 2017 Shaft/Bearing info

[Aaryn Swanson]

I'm just looking for insight if someone has done the 2016 upgrades to a 2014 and then had a bearing failure. Bearing was the stock 2016 from Yamaha, comes pressed into the housing arm.

 

[cannondale27]

Mine is still good. 16000 mi on now. If they were around when I converted to 16 setup I would have done the 17 setup instead.

 

[Aaryn Swanson]

Thanks for the response Cannondale, was curious as to your results specifically. At the time I was trying to avoid changing the back of the chain case (assuming I needed to in order to go with 2017 upgrade at the time). I'm actually starting to believe it was inner race of the bearing that spun and chewed through the snap ring that sits just outside of the bearing (clutch side). There was only a small bit of that snap ring left in the belly pan and it was paper thin. The adjacent washers and collar/spacers came apart, with the clutch still intact. The actual bearing races are still there, but the balls, cages and seals were very damaged. Housing looks okay.

Can you give me a more idiot proof explanation on how to specifically keep that inner race from spinning on the shaft? Thanks again for the help.

 

[cannondale27]

Thanks for the response Cannondale, was curious as to your results specifically. At the time I was trying to avoid changing the back of the chain case (assuming I needed to in order to go with 2017 upgrade at the time). I'm actually starting to believe it was inner race of the bearing that spun and chewed through the snap ring that sits just outside of the bearing (clutch side). There was only a small bit of that snap ring left in the belly pan and it was paper thin. The adjacent washers and collar/spacers came apart, with the clutch still intact. The actual bearing races are still there, but the balls, cages and seals were very damaged. Housing looks okay.

Can you give me a more idiot proof explanation on how to specifically keep that inner race from spinning on the shaft? Thanks again for the help.

That bearing is pressed onto the shaft big time. If that inner race spun either was wrong bearing or shaft was made wrong. How does your secondary look? It didnt hit the snapring did it?

 

[Aaryn Swanson]

I agree, as I bought the assembly with bearing already pressed in the housing (and on the shaft). There is evidence of the secondary rubbing against something, would almost have to assume the snap ring. I'll send pictures shortly.

 

[Aaryn Swanson]

 

[cannondale27]

Oh my! I think that was just catastrophic bearing failure. May never know why. Might need whole assembly again. Go with newer style to delete wobble bearing. Guys are doing it without back case replacement or a spacer. Personally I would run a spacer or new back case but haven’t heard of issues either way. Sorry to see your bad luck. It all gets us sooner or later.

 

[Mike P]

Those photos reinforce the need to PM all bearings and wear parts. Hope you get it turned around in time to ride it this season.

 

[Aaryn Swanson]

The frustrating part is that my entire setup had been upgraded a 1,000 miles ago, with a seasonal PM and replacement of all wear parts (top gear, grease, drive shaft bearings as well, etc) only 100 miles ago. Something happened to make either the collar, snap ring, secondary or the yammy bearing itself (2016 pressed into the housing at the factory; ordered complete shaft assembly last year) blow out.

Good news is, the 4206 bearing and 2016 upgrades (remember this is a 2014 sled) still looked great in the chaincase. I'm not taking chances regarding the shaft being bent, so I ordered the same 2016 shaft/bearing/housing assembly and all new parts past that secondary side bearing (collars/bushings, washers, etc). I was modestly confident that the 4206 bearing would hold up, but not having to deal with the 4mm spacer/6206 combo or the backplate upgrade needed to go the 2017 route, I'm hoping I just had a bad bearing from the factory. Have not upgraded to Winder chain and gear, but no whine, no usual wear; full turn out seems to be working.

FYI, Ultra Q exhaust makes doing this multiple times a year much easier!

MN next week and the back up to Munising the week after, will let you know if she blows again.

 

[cannondale27]

Part 2 coming in spring have more than double the miles without failure right now

 

[Mills]

If you get the newer inner case you are going to have to also get the M6 x 2.0 x 24mm bolts that go through the tunnel and thread directly into the back of the inner case. The bolts in your 2014 inner case are an M6 x 1.0 x 30mm thread and they will not thread into the 2016-2017 inner case. I know because I am doing this upgrade right now on my 2014 Viper. Who ever you get the inner case from, ask them for all of the mounting bolts also.
The bolt I am referring to is Item #38 in lower right hand corner of the exploded view below.

 

[cannondale27]

If you get the newer inner case you are going to have to also get the M6 x 2.0 x 24mm bolts that go through the tunnel and thread directly into the back of the inner case. The bolts in your 2014 inner case are an M6 x 1.0 x 30mm thread and they will not thread into the 2016-2017 inner case. I know because I am doing this upgrade right now on my 2014 Viper. Who ever you get the inner case from, ask them for all of the mounting bolts also.
The bolt I am referring to is Item #38 in lower right hand corner of the exploded view below.
View attachment 153435

Thanks Mills for the heads up. I went one better. I got the bolts and steel brace from 2020 6000r xc. Check it out.

 

[cannondale27]

Here

 

[YamaSpark]

Here
View attachment 153440

Do you happen to have the part number for that steel brace?

 

[cannondale27]

Do you happen to have the part number for that steel brace?

Arctic Cat #1142-0384 about $20