Motorcycle Repair: 1976 Honda 550 4, air fuel ratio, velocity stacks

Question
QUESTION: Hi Rich; The bike that sat for 17 Yrs. Completely dismantled the carbs, thoroughly cleaned. Will start up and run up to 6000 rpm,but only on full choke. Does not miss or buck until chokes are opened. Good supply of gas in bows, good flow, all 4 carbs affected equally.Studied parts illustration, all parts look accounted for.Outside of throttle linkage, not a complex carb. Any ideas? Thanks, Marcel

ANSWER: Marcel, the low speed jets or circuits are still plugged and the engine isn't getting fuel without the choke on.  You'll have to pull the idle jet and run a very small wire through it to clean it out. Just soaking them in carb cleaner won't always clean it out.

Regards
Rich

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

QUESTION: Rich, becuse of the difficulty of installing the velocity tubes, air box and air cleaner, I have been test running engine without these items. Any chance carbs will not function normally without these systems installed? Am I clutching at straws? Thanks! Marcel.

Answer
Yes, removing the velocity stacks and air cleaner will change the air fuel ratio and lean out the mixture.  It could cause a high speed miss or even burn a hole in a piston.  However, it won't cause the problem to the degree you are describing.

Regards
Rich