Hope someone has an idea. Had my 86/87 back on the road now for two months. I haven't touched the top end other than to reset the valves. Due to the climate & the nature of my bike I always set them 1thou loose. The carbies cleaned with carbie cleaner & the floats have been set to 9mm & pilot air & balance adjusted to speck.
Problem.... The bike has always been temperamental & randomly misses when taking off from the lights. Give it a blip & it's fine. Since the repairs on the bike it was bad on Shell fuel but good on Mobil. Lately I'm finding that it's shocking when cold & need to use just a touch of choke for up to 4 or 5 kilometers. At that point the bike is nice & hot & runs perfectly.
Head Gasket??? No oil in the coolant or visa versa. Air leak. Not running lean. Got me baffled.

 

Three things that come to mind up front;

(1) What air filter is in it? These bike is set up to run with a factory filter and may run a little lean with after market filter. I doubt that would be the problem.

(2) I need help with this one. Does your model have accelerator pump that dumps raw fuel in at the twist of the throttle? That is more likely the trouble. You would need to pull the carbs and cleanthe pumperif that were the case.

(3) Timming, is it set correctly and does it advance on takeoff?

 

Air cleaner is genuine. I must admit I thought about the accelerator pump a long time ago but forgot about it. I'll check but probably after Christmas. I'll check the timing to make sure it's correct & working. Amazing how you forget to check the basics. Thanks