Hi All,
In the last episode, the oil sight glass suddenly filled with oil whilst riding the bike. There was then a slight "clonk" from the bowels of the engine, but it passed quickly and I gingerly rode home.
Upon stripping the engine, I found that the oil spray bar had fractured at the thread near the pump, broken off after rubbing on the upper timing wheel teeth, and had escaped inside the crank chamber, to be mangled by the crank. All the bits have been retrieved, and a quantity of brass filings washed out of the works. There was plenty of oil in the two chambers, and no other damage seems to have been done.
This pipe was sheared off when I first stripped the machine, so it has "previous" for doing this. As this pipe is basically a resonant cantilever pole when only mounted at one end, is there a way of improving the design to obviate another failure? There doesn't seem to be a register on the far side of the crankcase for the bar to locate in, so would perhaps a steel tube be better than a brass one?
Any thoughts?
Cheers for now
Doug