I have a early 60's vintage HD 2 stroke. the motor has a custom made cylinder.145 psi,plug color chocolate brown,no death rattles or pinging, piston port with 2 secondary transfer ports,186cc,10:1 compression,TS 185 piston,58mm stroke,30mm delOrto PHBH carb, K&N pod filter,vintage expansion chamber,straight 16º timing (no auto advance)15t trans sprocket/52t wheel sprocket,black goo oozes from exhaust header clamp (but that is being remedied with a new gasket, then I am sure it will ooze out the stinger).
The first problem I had while dialing in the carb ,was the motor was loading up with gas in it's mid-range. Needle clip second from bottom on needle. I changed it to the top position as that problem went almost away. Spark plug is dry and a chocolate color.The bike runs really strong, but it gets outta the hole and builds up speed much better if I slip the clutch slightly to let the revs build little by little, then ease off along the way.The clutch works fine,doesn't slip or drag.
Is the mixture still too rich at 1/4-3/4 throttle. Why should I have to slip the clutch to make good out of the hole runs? Hope someone will shed some light on the subject here.Thanks