I posted before about a noise I get on start up from a cold engine. The engine sounds like a diesel for the first few seconds, then goes quiet and smooth as silk. There's no noise from over run and no abnormal running. This first started to happen when I did an oil change and I slightly over filled it, only about .25l. The noise has got slightly less over the last few weeks until today when I checked my oil level. It was still fine, 1 notch above min, but I had .25l left so I stuck it in. On start up the noise has come back again just as loud. What the hell could it be? Surely more oil would no affect the chain? The rocker cover is coming off in a couple of weeks to put an alloy one on as mine is black plastic, so is there anything I can check while the top is off? The noise does seam to be coming form the top/chain side of the lump. The lump has only done 20k. That reminds me, It was a new lump under warranty and when I first got it back it did it also, so again topped up with fresh 5w 30. The oil that's in there is only 6-7k old. I may be wrong but the colder weather does seam to help it also.