Servicing Shaft/Final Drive

[flatgrind]

Replaced the rear tire on a still fairly new to me 2012. Mileage on the bike is almost 40K. While I had the rear wheel off I decided to check the shaft drive. (My first time servicing a shaft).

When I pulled it apart I could see that it had clearly been wet. There was rust and dust throughout the inside and the lower inside bolt shows some dirt and corrosion. There was a bit grease on the splines of the shaft, so at least it wasn't totally dry!





Cleaned it up as best I could and greased the splines with Lucas X-TRA Heavy Duty as that was the only grease I had on hand, but didn't take photos.

I made a guess and torqued the acorn nuts to 30 nM / 22ftlbs.
I didn't realize that the rear wheel should be on first. Everything seemed aligned and the axel went in easily.

Now the questions:

1. What are the torque specs for the acorn nuts?
2. There isn't a gasket or seal that goes between the pumpkin and the housing that is connected by the 4 bolts and acorn nuts, right?

 

[Boris]

Now the questions:

1. What are the torque specs for the acorn nuts?
2. There isn't a gasket or seal that goes between the pumpkin and the housing that is connected by the 4 bolts and acorn nuts, right?

The acorns are 42nm.
Is the large rubber bung still in place on the inside of the rear brake side of the swing arm?

 

[flatgrind]

The acorns are 41nm.
Is the large rubber bung still in place on the inside of the rear brake side of the swing arm?

Thank you! Will tighten them accordingly.
As for the rubber bung, I had to go out and check. Yes, it is still there, I had never looked closely at it before. I pulled it out and it came out VERY easily, probably too easily, with a shower of dust and sand. Went back in a bit too easily too. Might need to replace that...

 

[flatgrind]

As a side note, when I removed the axle pinch bolt there was also a shower of dust and sand that came out. Not sure if it was just trapped down in the grooves, or if that actually could have come from inside the swing arm? Is there a drain hole or something there?

 

[Boris]

Thank you! Will tighten them accordingly.
As for the rubber bung, I had to go out and check. Yes, it is still there, I had never looked closely at it before. I pulled it out and it came out VERY easily, probably too easily, with a shower of dust and sand. Went back in a bit too easily too. Might need to replace that...

Sorry, it’s 42nm and it looks like no gasket,

 

[flatgrind]

Thank you!

 

[Boris]

As a side note, when I removed the axle pinch bolt there was also a shower of dust and sand that came out. Not sure if it was just trapped down in the grooves, or if that actually could have come from inside the swing arm? Is there a drain hole or something there?

I took my rear wheel out yesterday and quite a lot of debris dropped from that area too. I’m pretty sure there’s no drain there, just a build up from road spray.

I’m pretty sure that I read a post on here a while back where someone stated that their swingarm had two small holes along the bottom of the part that crosses ahead of the shock. The part that bolts to the frame. There was some suspicion that this is where the water was getting in and causing the dust/rust you describe.

 

[Boris]

Here’s some other common torque figures, including rear wheel, in case you need them.

Sump plugs - 20NM
Oil Filter - 17NM
Shaft Drain - 23NM
Shaft Filler - 23NM
Fork axle pinch bolts - 21NM - inner/outer/inner
Front Axle - 72NM
Rear Axle - 125 NM
Front calipers - 40 NM
Rear caliper -
Rear Swing Arm axle pinch bolts - 25NM
Rear brake torque arm - 30NM both ends.
Rear and Front shell speed sensors - 7NM

Top Yoke pinch bolts - 25NM
Lower Yoke pinch bolts - 20NM

 

[flatgrind]

I had everything for the rear wheel removal except the acorn nuts on the drive. Didn't have a couple of these, thanks!
I have a PDF of the Owner's Manual, but haven't found the Service Manual. Is it available as a download somewhere?
Thanks again for your help.

 

[Boris]

It is out there as a download, however I can’t recall where. Also, it’s frowned upon on the Forum to post links as it breaches copyright laws. Well at least that’s how I understand it.

 

[DamMechanic]

Clean up that rubber bung and silicone it in. The small drain hole on the drive side I have drilled and tapped but not tapped all the way through and installed a set screw to semi-seal it up.

 

[Don in Lodi]

There's a second rubber plug. It's up front, I thinks it's on the shock side. That tiny hole at the rear should be left open so all that muddy water has someplace to go. That's rust on the steel parts, looks like the muddy remnants from a submersion on the aluminum shaft housing.

 

[EricV]

The rubber bung fits loose from new, so as DamMechanic said, silicone it in place. Just a light smear of silicone RTV around the edges and pop it back in works fine. Don't block off the drain hole, water will get in there, it needs to be able to drain back out.

For future reference, the splines like a moly based grease for high pressure. Don't stress about it now, just do that next time. I typically smear a light coating of grease along the drive shaft for rust prevention too, and do the same on the axles. I know they are not bearing or contact surfaces, it's just about keeping the corrosion away.

If that was your drive shaft condition, you might want to consider doing the swing arm bearings next time you pull it all apart too as a preventative measure.

 

[Boris]

Am I right in saying that the 4 acorns should be torqued once the wheel is back in and fully tightened up? I seem to recall this from a much earlier thread on the pumpkin removal thread. I have I understood this correctly?

 

[flatgrind]

Thank you. Won’t block the drain hole. Definitely don’t want to trap water in there.

Like you, I also put a thin film of grease on the shaft surface for hopefully some corrosion protection.

Went to two stores looking for moly grease, but neither had any in stock, so I used the Lucas HD, which I’m thinking will be fine for now and not present any compatibility issues when I get my hands on some moly grease.

Swing arm bearings are a good idea. I’m going to do that next time, maybe even before the next tire change. I recall reading in some other posts that the swing arm bearings often have a “solid” grease/lubricant in them that has confused some folks.

 

[Boris]

There's a second rubber plug. It's up front, I thinks it's on the shock side.

I didn’t know that! Just had a look and sure enough, there it is. Wheel side of the shock, behind the little spray guard thingy.

thanks Don.

 

[RCinNC]

One thing I do when I do the swingarm maintenance is to make an alignment mark between the swingarm and the final drive using a white out pen before I start disassembling anything. It's a nice visual reference that you have the final drive back in the correct position when you put it all together. Of course, the accuracy depends on whether it was aligned before you took everything apart...

 

[Don in Lodi]

Am I right in saying that the 4 acorns should be torqued once the wheel is back in and fully tightened up? I seem to recall this from a much earlier thread on the pumpkin removal thread. I have I understood this correctly?

That is correct.