Final Drive Disassembly

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First off, better pictures and tutorial here BUT its not in english but still very valid.

Here is a discussion on the subject: Hobbit - Final Drive Disassembly

This is a quick overview on how to take a Honda PA50 or PA50 II final drive apart.

Skill level required - 3/10
Tools required - Nothing special
14mm wrench (oil drain plug)
10 or 12mm for selector arm
screwdriver with JIS bit or #3 
Mallet
Vice
Torch (Bearing removal)

You have to remove the rear wheel from the hobbit subframe

Quick overview

4 bolts on final drive ( 2 have nuts, 2 have them built into the rear drive ) remove the tensioner for the chain, remove the belt

Now you have a big wheel with the final drive. Hammer on that 7/8 12pt socket impact it off with hand on the wheel / rim. slide the break hub off, now your getting there.


Dis-assembly

Drain the oil by removing the 14mm bolt in the middle of the housing.

Finaldrive1.jpg

Scribed a line for the position of the arm and remove the arm. I did this, maybe you don't need to. Hobbit final drive 1 1.jpg

You also need to remove the rear pulley. I would use a strap wrench on the thing or an impact and then the correct threaded puller so you don't bend the pulley.

Now unscrew the 5 JIS screws. I used my craftsman screwdriver to take off the screws. The bit was a #3 Phillips though. I had to use the blk wrench to get torque on it! Impact driver would be ideal

Finaldrive2.jpg

Now you need to separate the halves. To crack it apart, you gotta hit it. Maybe rubber mallet. A few smacks with some firewood worked for me. Clamped it in a vice on one of the bolt tabs and rocked the case back and fourth a few times and had no problems.

Finaldrivesplit.jpg

Finaldriveapart.jpg

So with the two halves there is a couple of washers to take note of. There are a few shafts & gears that sit in their own spaces! Very important to place them back correctly.

FinalDriveHalf1.jpg

FinalDriveHalf2.jpg

So at this point you may as well remove the bearings and replace them. Its cool with me! Heat up the inside, or outside of the case, smack them to the inside, done.

Honda final drive Bearing removal.jpg

Washer locations!

Washers1.jpg

Picture of the tricky output shaft assembly

Outputhalf.jpg

Cleaned up cases

Cleaneduphalves.jpg

Washer Specification

2 x Small washer @ .95mm thick, OD 18.6, ID 10.34

1 x Large Washer @ .98mm thick, OD 27.92, ID 17.16

Replacement Parts

These are the Honda OEM parts for the seals and bearings. Yours may or may not need replaced. Check your local honda dealer for bearings, or order them yourself from a trustworthy shop. Oil seal dimensions are in metric (e.g. "24X34X5.5" means 24mm inner diameter, 34mm outer diameter, 5.5mm thick)

For the pulley side,

BEARING (6201) 96100-62010-00
OIL SEAL (12X22X5) 91201-965-000 

For the brake side,

BEARING (6203) 96100-62033-00
OIL SEAL (24X34X5.5) 91203-148-003

There are two of these needle bearings on the gearshafts:

BEARING (1010) 91021-148-004