my mates who know about more bikes than me said they checked the head gasket and that it was ok. Have checked the hoses around and have found a few places where there is a little wetness, so it might be a tear or hole somewhere in the hose. Also, the guy i bought it off had an air filter but it had like holes in the bottom of it, so it could fit in the air box, since the air box has like little prongs, so im guessing he needed to make the holes on the air filter in order to make it fit into the air box? Does anyone have a picture of an OEM air filter, not sure if i want holes in mine.