Monday, 20 June 2011

Mystery Solved...I think

Over the week end I took apart the final drive piece by piece.
I was trying to find the source of the lose bearings I found inside the case.
The problem was all the bearings in the final drive seemed to be intact.

The one thing I did not take out was the shaft drive from the engine where it goes into the final drive case.
So I started to take that apart and found a bearing that was lose.
Gave it a wiggle and several ball bearings feel out that were the same size as the ones I found inside the case.
This got me to thinking and I remembered Dom had sent me all the spares he had when he sold me the bike. This also included several replacement bearings.
I took a look and found one that was the same size as the prop shaft bearing.
But the new one was a double row bearing. The one on the bike only had one row of bearings and was very lose. I looked at the parts diagram and the part was called “Thrust bearing -Double row”
I also notice the u-joint on the axle was stiff in one direction also.

Keep in mind this bearing is right in front of where the prop shaft and final drive gear meet.
Think of an egg beater going in two different directions at once. What I think happened was the last row of bearings failed and when it did it got chewed up and spit out into the case. The bearings were held in with a inner brass piece. Which would explain all the little brass flakes all over the inside of the case.
When the bearing got chewed up I think it sent the ball bearings spinning around inside the case like a frag grenade. Which probably also tore up several seals in the process.

What's amazing it he fact that the wheels kept turning after all of this had happened.

I called Holopaw Ural today in Florida and ordered new seals, a u-joint and I hope all the parts I need. Once I get them I'll start putting it all back together and hope it works.

1 comment:

  1. Outstanding detective work Michael!

    That is the one component I didn't take apart when I repaired the final drive. It makes me feel a bit better that it wasn't something I did that caused this bearing's failure.

    Glad to hear Holopaw had all the parts required as well.

    Looking forward to hearing Tasha is back on the road.


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