Went to the Huddersfield meet yesterday, and on the way home I noticed some black smoke coming out from the exhaust when giving it some gas. Must have lasted a couple minutes and then it was clear, bit like what diesels cars do when they put there foot down. And when I was coming to work this morning I noticed blue smoke from the exhaust , when i was coming down a hill and putting on the gas at the bottom of the hill. I thought this might just be overrun, but when I put the clutch in and stepped on the gas pedal it was doing it again. Did this a couple of times but then stopped, tried it few t