- May 12, 2008
My 75 Mk3 recently developed a problem with coughing and sputtering, especially at low throttle, but sometimes at mid throttle. She has become hard to start, but does start eventually. If I take it off the choke too early (5-7min) she dies. Used to idle really nicely too... The strange thing is that I have to stay on full choke for the first 10-15 minutes of riding, but then after a few minutes at 1/2 to 3/4 throttle she returns to normal... so it's as if I can 'ride through it'. As long as I keep the engine hot it's fine, but if it cools all the way down, the problem returns. I had the carb off and cleaned the pilot jet, sprayed the carb with carb cleaner, and she ran fine for a few days. Timing is good, but the plugs are a little darker than I like... but they're not bad or wet. The rods that the floats ride on have a tiny bit of discoloration near the top, but the floats seem to side on them fine. Any ideas?