Took my Benelli 491, minarelli L/C 50 apart, and fitted a new crankcase from an aerox because the calliper had snapped off the old crankcase. I've fitted the Benelli's piston and barrel as it had done considerably less miles. I gave the crank 20ml of oil (poured it in), and gave the barrel and pison a good coating of oil aswell (about 1mm thick coating). I also put 100ml of 2 stroke in the petrol tank. Firstly it idled fine for about 5 minutes. Then cut out. Then it took quite a while, and a lot of kicks to get it started again. It would idle unevenly, reaching high rpms, then low rpms, then high rpms before eventually cutting out. I've got it to idle fine now by adjusting the idle screw. However, when I apply some throttle, it doesn't seem to respond too well. Lots of white smoke comes out of the exhaust, and when i put my hand next to the exhaust, it got covered in black splutters. The plug colour was a wet black when I checked it. What I'd like to know is whether this could purely be because of all the excess oil in the barrel and fuel tank, or whether it coule be an air leak somwhere (e.g. reedblock). Thanks for any help
Most likely build oil as after that amount of it in there for that little motor its gonna smoke for a while, but I like your thinking. Just also check the inlet connections and torque the barrel. Then let it run up and get warm a few times and eventually the smoke will thin out. You'll obviously have to set the carb up again after its cleared as you can;t possibly set it right with the excess oil still in there. Well done for rebuilding it yourself too :up:
yeah sounds like excess oil to me as well!!! take it on a good run to clear it out....take a plug spanner as well in case the plug oils up again....might save you a long slog pushing the bike home!!
