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Cb750k 6 carb bench sync

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Trigger:
If any small bits left on top of the piston ( very unlikely ) Start the bike up with all 4 plugs in but,not the exhaust of the cylinder that has been re tapped. You need pressure from that cylinder to throw anything out with a quick blip of the throttle. 

Paulreade:
Appreciated guys. Thanks
Paul

Paulreade:
By way of an update, followed everyone's advice, appreciated as ever.
Bench synced carbs, adj timing chain and reset the points etc.
Started her up and she fired first time. Ran her today and the knocking I had which was reduced when I replaced the clutch has now all but gone. It literally sounds like a sowing machine. It must have been the carbs slightly out of balance (no4). Quite amazed how smooth the engine is now.

K2-K6:
Interesting progress and all sounds good.

The elegant simplicity of that bench syncing method,  without special tools and using the same drill bit, really does take out all the variables of the carb operating mech.

Certainly if they are off the bike I feel it's the most accurate way of setting them. In service, installed and running, then vac guage method is viable just from a convenience point of view,  but it holds no greater accuracy than diligent setup.

From discussion we've had before, it seems like they originally arrived at production line set like that and ran perfectly.

Honda's "icing on the cake" in setup was to adjust the idle air screw to equalise the tickover and slow running. Described in their original manuals,  they accept up to 1/8 turn plus or minus on the air screw setting to calibrate each idle circuit. 

The main syncing is after all a method of getting parity to each cylinder for air volume under maximum load, smooth tickover in a consequential byproduct of that. It's not the principal reason as generally viewed in so many discussion of multiple carb sets.

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