Well, repairs anyway.

When getting to the end of a job don't hurry. It is tempting to force through the last bolt. Don't, if you feel resistance and it is clean then stop. Go get a tap and tap it out first. Then finish the job.


There were three main areas of concern. The first was that the gearbox bearing had been forced in at an angle. When checking the run out on the primary chain the chainwheel was found to be 0.040 thousandths of an inch furthur to the outside than the drive sprocket. This was a mystery until the bearing was removed. Even after heating in an oven for an hour it was still problematic getting it out.

Aluminum distorted

Not a great picture but look closely at the bottom left. Into the corner there is aluminum piled up from the bearing pushing wrong. This was removed after a lot of labor with dental tools. Some of it was swarf. The bearing did not seat all the way but was left .040 in from going all the way in on that side. See the next picture to see what was removed. The small lines were smoothed even with a very small, soft abrasive rubber wheel one at a time. The bearing clunked in nicely after the case was warmed to 200F.

Aluminum removed

The second was the outer race of the drive side bearing had been forced in at an angle. It was not possible to remove it without drilling three holes. It would have been nice to use small holes but they didn't work until enlarged. Thank goodness there was a tig welder here that works on the Border Patrol helicopters and knew how to repair it properly, including the radius fix on the seal and bearing races!

Bearing removed and case repaired

He indicated the holes not be filled near the race but most of the work be done on the outside.



The third area of concern was how to get the water out of the outer cover of the gearbox. I learned how to make this bodge from the postings of:

Mr. RF Whatley on the Brit Bike Forum.

He explained that to do this drill a 3/8 hole through the inner cover as shown in the first photo. This is how I did it on the 1966 Bonnie but the second picture shows how I improved it some by moving the hole down a little.





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