Last Monday, I went out with the local mcc for a run. It was a hot day. When I started the bike at home, it started 2nd kick and I went to the meeting point. On trying to start it to go on the run, it would not co operate and fuel poured out of the rear carb which stopped when the float chamber was tapped. Eventually, we bump started it and it ran perfectly on the run.
I stripped the carbs and cleaned them but found that the plastic floats were catching on the left hand lower screw boss of the float chamber and this was causing the flooding. The plastic floats have a flash on the inner end where the end cap is attached and the end cap is a slightly larger diam than the rest of the float. I had a pair of copper floats and on fitting these, there is appreciably more clearance and it cured the flooding.
I assume that the carbs had emptied themselves by evapouration as a result of heat soak from the engine and the hot day allowing the floats to drop down low enough to catch the float chamber.
I don't have the standard fuel pipe routing and also suspect I had a vapour lock to the front carb which combined with flooding of the rear, meant no fuel was reaching the front.
I stripped the carbs and cleaned them but found that the plastic floats were catching on the left hand lower screw boss of the float chamber and this was causing the flooding. The plastic floats have a flash on the inner end where the end cap is attached and the end cap is a slightly larger diam than the rest of the float. I had a pair of copper floats and on fitting these, there is appreciably more clearance and it cured the flooding.
I assume that the carbs had emptied themselves by evapouration as a result of heat soak from the engine and the hot day allowing the floats to drop down low enough to catch the float chamber.
I don't have the standard fuel pipe routing and also suspect I had a vapour lock to the front carb which combined with flooding of the rear, meant no fuel was reaching the front.