1944 M20. I just woke her up from winter hibernation. She’ll start fine and idle well for a minute or so and then stumble and die if I don’t rev the throttle to keep her going. She’s also backfiring a bit. Been stored for the winter with a full tank of ethanol free gas with a fuel stabilizer. Any advice is greatly appreciated before I tear into the carb. Thanks in advance.

something could be blocked, might be wort cleaning out the fuel jet and make sure your getting fuel through

Thanks Barry. I just went through this with an Amal off of a Triumph that had sat with fuel in the tank and carbs. Probably a pilot jet issue but I don’t understand why it starts up and idles nice for a minute or so and then stumbles.

Water or crud in the float bowl banjo?

Rob

email (option): robmiller11(a)yahoo.co.uk

Thanks Rob for the suggestion. I started to remove the carb and found the manifold nuts had loosened up. Odd, because I had sprayed carb cleaner there and didn’t hear any increase in revs. Should have been the first thing to check. Thanks for responses.

thats good, always check the simple things first before you narrow it down to a mag rebuild

Agreed. Last time I rode the bike in the fall, it ran fine. Don’t understand how the nuts loosened up. Must be the vibration or I have a gremlin in my garage.