Re: 1981 Honda CB 750 K

Posted by seestheday on Mar 04, 2013; 4:51pm
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/1981-Honda-CB-750-K-tp4037344p4037347.html

The fuel squirting out of the carb - is it coming from the nipple on the bottom of the carb (a hose is likely attached to it).

If so, this is probably a stuck float valve, caused by having old gas sit in the carbs over the winter.  Did you put fuel stabilizer in before you stored it?  Seafoam might fix it, if not, you need to pull and clean those carbs.

Black smoke usually means an excessively rich mixture.  Too much gas and not complete ignition.  You stated that you likely flooded the engine with gas before it fired, this likely caused the black smoke.  That might work itself out after a short run.  Don't do a 100 mile trip or anything like this though as you'll get excess carbon build up.