I and others have experienced this problem with 4-strokes, namely a couple of Norton twins and a T110, on hot days, on different occasions. It is quite baffling. The only conclusion we came to was fuel vaporisation. We were able to get them going by removing the plugs, squirting neat fuel into the cylinders, rapidly replacing the plugs, whereby they fired up, drawing fuel through, and all was right with the world again! This actually happened on one occasion to both of us at the same time, on a ride out where we had a short stop, and neither a Norton or the Triumph would start. We had sparks, but the plugs were dry.
Interesting about summer and winter grades of fuel, Ian. The Norton was using standard pump 95 ron ethanol-laced petrol, whilst the Triumph had Esso superunleaded 97 without ethanol.
Ian
Interesting about summer and winter grades of fuel, Ian. The Norton was using standard pump 95 ron ethanol-laced petrol, whilst the Triumph had Esso superunleaded 97 without ethanol.
Ian
Comment