Piss Poor Bearings..Only 154,614,000 Revolutions

[Rio Wil]

I will post a photo of the piss poor bearing after I cut it open tomorrow....rear left side, only 206K miles
OEM trash!!!!....put a nice Chinese one instead....cause I had it handy.  This bearing was still smooth 10K ago when I last checked the splines.

Although I didn't clean all the balls, I didnt see any pitting or wear on them......maybe a little bit of heating.

Here is what it looked like upon cutting apart.....no sign of rust from water intrusion




Here are the races cleaned up....surprisingly, the outer race was still fine.



The inner race had the pitting  and not shown, the opposite side had began to show signs of heating.





New bearing with the seal removed....kind of clear-blueish grease.



View from other side...note the difference in amount of grease







The beginnings of "red rust" forming.......



Thrust from the drive shaft contacting the front of the pinion shaft creates heat, burns off the
carrier in the lube, metal particles turn reddish and the cancer starts to spread. Left unattended to, it will creep down and around to the splines and completely encompass them.
I have never had a p/c that lubed its self from the final drive.....some have??  



This was after 10K miles.........



Brain Storm......wonder if it will help.....1/8 thick felt and saturated with grease after this photo taken. Not too hopeful, centrifugal force being what it is.....



Walla!!!!! final drive up nice and high.....took 4 seconds to stab the drive shaft/u joint.....a personal BEST.....

[The emperor has no clothes]

Very interesting idea with the felt . Be interested in how it works. My personal best is 2 seconds but I've also had a 30 minute stab also

[saddlesore]

Wouldn't the felt washer prevent the shaft from going into the cup all the way? 

[Rio Wil]

There is sufficient room for the oring keeper  to lock the shaft into the cup....and still has a little play.

[Rio Wil]

Added pic's of the bearing in the original post.

[Ricky-D]

I'm missing it!

What's the reason for the felt?

***

[Rio Wil]

An attempt to keep a little grease in or around the contact point between the end of the drive shaft and the front end of the pinion shaft where the pinion nut is.......next time you have the final drive off, check the nipple worn onto end of the pinion shaft and apparently this contact point gets hot enough to boil off the grease and start creating red rust.....JMHO

Also, from the dried out condition of the grease in the failed bearing, I will be replacing the original double row bearing at the next final drive inspection.....grease in it can't be very good.....206K is good service...cant complain.

[Ricky-D]

During an inspection I noticed that the end of the pinion shaft

along with the end of the drive shaft had a nice shiny polished

appearance. I surmised the two were in contact and that was the result.

There was no abrasive look at all. 

I think the felt may contribute to contamination in some way.

***

[Rio Wil]

I suspect it will slowly get ground up into a fibrous mass.......but if that mass retains any lubricant around that contact point....maybe that's a good thing.  On both of the final drives I have, it is more than just a shiny spot.....about 1/8 of a inch has been worn off leaving a corresponding nipple sticking out. All the metal that was worn off was captured by the grease and presumably migrated to all the contact points on the splines. I would like to see a way to increase the maintenance interval for the final drive/pinion cup increased to say 30K.....maybe only have do it once a year instead of twice or three times.  More riding....less work..

[Rio Wil]

SO THE MORAL TO THIS BEARING STORY IS::::: IF YOU WANT YOUR BEARINGS TO LAST FOR A HUNDRED YEARS, POP THE SEAL OFF AND ADD SOME FRESH GREASE SO IT DOESN'T HARDEN UP....