hi Graham. i had the igintion case off yesterday i noticed the littel breater hole on the gearbox was blocked so i cleaned it out. as for the oil leak i think i may be coming from the seal behind the sprocket but before i take the sprocket off just going to see if its still doing it. dosant leak when its runing only when the bike is over to the L/H side i dont know maybe theres abit to much oil in there i did drain it.and i only put 500mls back in should take 550mls on a drain.and refill. anyway the bikes not being used so am not worrying about it need to sort the rear wheel out on that 1 needs new tyre inner tube as i blow it yesterday Opppps.