Progress today
Bled the rear brake caliper by the manual method. Pumped the pedal and bled to Mityvac hose without pumping any vacuum pressure. Saw bubbles in the fluid from the nipple the first couple of cycles, then none after. Nice firm pedal feel and the brake works now.
Loosened clamp and removed choke cable at the carb end. Unscrewed the manual idle adjustment cable/screw from the carb assembly. Left the knob and cable on the frame.
Loosened all 8 carb boot clamps. Soaked each boot with WD40 to help them slide. Levered carb assembly up off the boots – two rear cylinders forward first, then front ones back/up.
Once carbs up off the ports, removed the throttle cable holder and pulled cable ends from the carb wheel. Cables now loose enough at the handgrip to remove and clean that assembly, as well.
Carbs on the bench. Will have to determine minimum disassembly needed to clean all passages/jets and change out o-rings and seals. Noticed that float bowl screws, at least, are JIS (Japanese Industrial Standard) types. Will get the right screwdrivers before attempting to loosen those – they are very tight.
carb assembly, underside
A little worried that the choke mechanism doesn’t move much. Can’t see any obvious problem, but not sure how it’s supposed to work, either. Needs investigation. I hope I haven’t bent something while levering carbs off the intake ports.
Thermostat housing also now accessible. Will replace thermostat and clean housing while we have access.
Took a look in one of the ports (#2). Not much to see, at least nothing alarming.
The engine “v” needs a good vacuum and clean, too.
Then stuffed paper towels into intake ports to keep everything out while apart.