I have just finished bolting together my M91 sherpa and have a query at the moment it has no airbox on and is being run with an open carb (not ideal I know) but I noticed exhaust gas coming out of the carb is this normal and if not what would it point to the engine has been professionally rebuilt (new piston, mains, big end etc) and the carb is the original amal 627

Thanks

Pete

It should be just fuel vapour you're seeing out the back of the carb, not exhaust gas, which is normal if you're running without the filter attached. I've seen it many times out the carb on my Ossa when giving it a quick run around the garden without the filter on.

Do get some fuel vapour too so that sounds ok then. Just all the niggles to sort now I bought some levers from a well known supplier and my cables (from the most well known cable supplier) dont fit right and the lever adjusters and ferrules need "adjustments" to tweak them in.