pulled it apart today, both plugs are brown and dry, no obvious kinked vents, carb diaphragms look fine, fuel lines appear to be flowing fine. carbs well seated,no cutsin boots,etc nothing looks obviously wrong.
Smoke, some residue on rear cylinder exhaust from crank case breather being moved to a seperate filter at back cylinder. Rear cylinder(one i changed shims in) nothing obvious, everything still in spec.
Oil level looks good, coolant looks good, throttle, choke cables all moved freely.
Kinda stumped at the moment, not going to push my luck with it. going for the "ride of shame" tomorow in the bed of a truck!
both plugs looking so lean(did not look dry/brown at service) leads me back to a fuel delivery issue. fuel pump? as far as the smoke/chain rattle, we shall see!
i will update as i discover the issues for future reference!