Motorcycle Repair: Harley FLH - misfiring, harley flh, intake leak

Question
QUESTION: Hi
Have a HD FLH year 72 wit SS Super B carburettor on. At low speeding like 20 - 40 miles pr. hour and almost no gas on the handle - the bike misfires now and then , not with a bang from the exhaust , no its just more like the ignition is missing suddenly for a splitsecond for a period of 2 -3 times in a row . The igniton timing is okay - so are the points. Is it the air mixture adjustment perhaps ?
When driving at highway at higher speeds theres nothing wrong.

kind regards
Carsten

ANSWER: Pull your plugs and let me know what color they are
Mike

---------- FOLLOW-UP ----------

QUESTION: Hi Mike

They are light brown in the color. The exhausts smokes a bit in slow running.

kr
cn

Answer
The air/fuel misture screw only affect the bike at idle. Check for a intake leak by spraying some carb cleaner around the intake after the bike has warmed up. If the RPMs go up them you have a leak. Also, your points might be burned or the condenser is bad
Good luck and happy riding
Mike