Folks
I've finally gotten the K2 engine to the point where the cases, barrels and top end are oil tight. It'd be fair to say it's fought me every step of the way, and even though it now runs really nicely, it isn't prepared not to let some oil go from out of somewhere on the lower left hand side.
I know the gaskets in that area can be a pig, and I've already had to replace the generator gasket for one made from thicker material; before I put the side covers back on, I made sure the mating faces were completely uniform by wet 'n' drying them on a very flat surface. Turns out I might have removed fractionally too much from the generator cover (or the gasket I used was crap) 'cos one of the generator assembly faces met with one of the coil faces. Thicker gasket cured that, and I'm going to replace the shifter assembly cover gasket to match.
Anyways, I think the oil is probably coming from around the neutral switch. When I originally relocated the switch, I found that a brand new 3mm Honda o-ring (specific part) didn't compress and/or allow the switch assembly to sit deep enough in the recess for the switch itself to work - in other words, the bike could be in gear, but the neutral light would still be on. I swapped the o-ring for one out of a generic metric kit which is 2.5mm thick, and that cured the light operation problem, but it looks like it's the cause of my leak.
So what are my options? I guess I need an o-ring with a 3mm thickness left to right, but with a smaller thickness top to bottom. My instinctive response is that there must be a way of shaving down a standard o-ring, but that's a pretty imprecise science. I've also had a look to see if I can find something else that would replace the original, but so far I haven't turned up anything suitable.
Ideas/suggestions/pointers gratefully received - and help me put this issue to bed once and for all . . .
Thanks