Final Drive Bearing Replacement

Ossaboy2867

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Joined
Jan 24, 2017
Messages
80
Location
Wellsville NY
I removed the differential today to replace the leaking seals. I think I may have destroyed the rear end in this thing....I noticed after I got the unit on the table and the driveshaft out, it may not just be dirt and grime causing the seal to leak. Any differential I have seen, car or bike should not have any lateral movement here.174F26C7-6897-4687-88BB-3AB48F3971B7.jpeg
Has anyone ever heard of these rear ends failing? I ride a ton of offroad and rip wheelies all the time on it. The last ride I had on it had no noises or nothing indicating a problem, other than the oil, which was full when I got back and noticed the oil soaked dust.

Thanks in advance, feedback welcome.
 

Jlq1969

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Joined
May 5, 2018
Messages
506
Location
Argentina
Video of movement

The problem must be number 11 ... when a seal fails, in 50% of that failure, the bearing is usually the cause
Probably (15) inside the fork, if it fits tightly, stop having that radial movement. the important thing would be that the pinion does not have that radial movement and in the video a small radial movement of the spring can be seen
5C685BFE-D46E-4486-97DA-963BB5F5919F.jpeg
 
Last edited:

Ossaboy2867

Member
Joined
Jan 24, 2017
Messages
80
Location
Wellsville NY
The problem must be number 11 ... when a seal fails, in 50% of that failure, the bearing is usually the cause
Probably (15) inside the fork, if it fits tightly, stop having that radial movement. the important thing would be that the pinion does not have that radial movement and in the video a small radial movement of the spring can be seen
View attachment 61868

Almost certain its the bearing. I can see movement in there after I removed the coupling. I need to manufacture the “specialty” tools to dig in deeper.
 

navynuke

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Dec 16, 2013
Messages
292
Location
La Habra, CA
Almost certain its the bearing. I can see movement in there after I removed the coupling. I need to manufacture the “specialty” tools to dig in deeper.
Mine failed while under warranty still. Took about a month due to dealer not having the special tool

Sent from my SM-G892A using Tapatalk
 

madman4049

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Joined
Sep 10, 2018
Messages
104
Location
Northwest Louisiana
Current issue aside that's really clean and healthy looking internally, how many miles are on your bike? I'm curious because I believe I remember you saying you wheelie alot and ride like a hooligan, I do to so just curious. My final drive oil is usually pretty nasty and I change it every time I change engine oil.
 

Ossaboy2867

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Joined
Jan 24, 2017
Messages
80
Location
Wellsville NY
Current issue aside that's really clean and healthy looking internally, how many miles are on your bike? I'm curious because I believe I remember you saying you wheelie alot and ride like a hooligan, I do to so just curious. My final drive oil is usually pretty nasty and I change it every time I change engine oil.
I almost have 30k on the odometer now. I honestly believe it failed because the big seal retainer was not tight at all. I recall the manual stating that ring needs to be around 100 foot lbs? I will check when I get home. Had that not loosened up, I think it would be fine. The reason its so clean is because I had just flushed it out in September. If your curious about anything else you want me to check, let me know.
 

madman4049

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Sep 10, 2018
Messages
104
Location
Northwest Louisiana
I almost have 30k on the odometer now. I honestly believe it failed because the big seal retainer was not tight at all. I recall the manual stating that ring needs to be around 100 foot lbs? I will check when I get home. Had that not loosened up, I think it would be fine. The reason its so clean is because I had just flushed it out in September. If your curious about anything else you want me to check, let me know.
Wow that's a whole lot less miles than I thought you were gonna say. You are correct on the torque, it is 108ft lbs I looked it up in the service manual pg 4-115. Makes sense on the recent flush thanks for answering my curiosities, good luck with the repairs.
Final Drive.JPG
 

RCinNC

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Joined
Aug 30, 2014
Messages
1,627
Location
North Carolina
Ossaboy2867, can you provide some specifics about the size of the socket you bought and what machining you did to it to make the special tool? It's good to have alternatives, just in case one of us ever runs into the same issue as navynuke and gets sidelined over the unavailability of the tool.
 
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