The Free Kawasaki Z650 Project

See if the solid vloat needles have rubber-tipped replacements. Rig up an auxiliary fuel supply (no more than half-litter needed), and use 91% isopropyl alcohol with the rack off the bike to test for leaks and that the bowls are filling properly.
New float valves and seats fitted, carbs back on the bike, and it now runs. but only on three cylinders. The dead cylinders carb has fuel in its float bowl at the correct height, while the spark is ok too. As it ran on 3 cylinders, I squirted fuel with a syringe down the carb and that cylinder fired up for a few seconds until the fuel ran out.

Today removed the carbs yet again, stripped that carb and put it in the ultrasonic bath for another 30 minutes. Couldn't see any problems so rebuilt the carb, and will try again over the weekend. Though I'm not expecting too much..
Ultrasonic often needs assistance with mechanical gentle cleaning to remove solids and really hardened varnish. Should be able to squirt brake cleaner through every jet, orifice, and passage.
With the problem carb back on the bike, it still ran on only 3 cylinders, however the green F2 carbs were very clean, so I replaced the carbs on the bike with the F2 carbs and without much hope, hit the starter.... and the engine sprang to life on all 4 cylinders for the first time! I still have no idea what's the problem with the no1 carb off the bike, but now I know for sure the fault lies with the carb and not anything else.
While there are a few small items that need to be done, such as rechroming the kickstart and brake lever next winter, the Z650B is now completed.

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