This is on a mountainbike, has a cheapy cup and cone bottom bracket. What happens is when pedalling (especially on the smaller rings) there is a popping noise when the right crank arm passes through the 11'oclock position. The crankarms/pedals are not hitting the frame and the front cog is also not hitting anything on the frame.
It becomes less pronounced as you shift higher and is undetectable under force (say under acceleration) in high gear. It is very evident when pedalling lightly in low gear. Take it in for service? Or is there something I am overlooking? I don't have the tools right now to take apart the bottom bracket at the moment.