Final Drive Project
I'm concerned that re-shimming my rear end may not have solved the problem. I've decided to find and prepare a replacement final drive should my current drive continue to shed metal bits.
This is the drive I found with the help of some friends. The drive
splines look good. The case is dirty, and ugly, but should clean up nice.
The real question is what will the gear set look like. The only way
to know is to pull it apart and take a look.
I removed the brake shoes. The friction material looks almost new. I
cleaned the friction material up with some brake cleaner and then wiped the
shoes (but not the friction material) down with a rag dipped in WD-40.
They cleaned up real nice. I might put these shoes on the bike as the
current shoes are using a friction material that is made for hydraulic
applications.
There was no gear oil to speak of in the drive. The drain plug isn't the
magnetic type; couldn't look for metallic splinters. The nuts holding the
case were removed and the case opened using the appropriate puller screws
from the Ed Korn Many-in-one tool-kit. The remains of the paper gasket
looked like it was turning to mildew in some spots.
Some wooden blocks were used to hold the cover off the bench while I applied
heat until the crown gear fell out of the cover. Curious, I measured the
case temp as soon as the crown gear fell: 285 degrees F. I also measured
the current shims. The brass thrust ring to set backlash is 2.36 mm,
the crown gear bearing shim is 0.63 mm. 0.63 is a standard size for a
"spacer washer" according to the parts book, but the standard sizes for a
thrust ring are 2.3 mm and 2.4 mm. Seems the part in this drive has
turned into an in-betweener.
I pulled the bearing from the crown gear and cleaned it up. I think it
will have to be replaced. There is a rough spot. I'll try cleaning
it some more on the off chance the roughness is a bit of dirt. I'll also
looking at it under the loupe.
The cover cleaned up quite nicely with some simple green, WD-40, and a
scotchbright sponge. The breather hole was plugged solid. A pipe cleaner
helped get it free of grunge. I dried it with the help of compressed
air then wiped it down with WD-40 and put it away.