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carb synch

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ogre:
hi all nearly finished my resto of my cb750 1970 will post piccies when done been doin it for 2 years on and off an hour here and there got to keep everybody happy. anyway got engine runnin synched the carbs got good tickover at 900 rpm no black smoke but the plugs are black. does it need a run for a proper check its not quite finished to do that at mo. the air screws are out about 1 1/8 turns when its warmed up and i blip the throttle it hesitates so i thought it was the throttle cables which needed setting i did set them before i put airbox on and ran it. so according to manual open the throttle and read the gauges and adjust. on 1 and 4 carbs the vacuum dropped on the gauges dropped reading more vacuum as soon as i opened throttle. 2 and 3 carbs went slightly up on gauges but it seemed to rev a lot better than when  adjusted 1 and 4 to go slightly up on gauges the same as 2 and 3. it really hesitated cant get 2 and 3 to drop like 1 and 4 no adjustment left on carbs is the engine to hot or is there summat i,m missing the throttle cable is new 1 to 4 cable type any help would be appreciated.     

Bitsa (Ralph Wright - RIP):
Hi
Are we talking k0?If so what little knowledge I have is what I have read.Others I am sure will correct me but I would start off with tickover screws get them all in spec with the guages then with throttle just open tighten cruise screw on rh switch then adjust all the tops of carbs of slack.Loosen off cruise then open a wee bit and see if vacuum guages rise the same.
Cheers
Bitsa

ogre:
yes its a k0 i take it you mean the little screw underneath the switch i did set throttle screws got the gauges spot on 21 cmhg ticks over ok at 900 rpm i also set 1 and 4 carbs to middle carbs but was worse on hesitating when i opened throttle

ka-ja:
Hi,
     Have you synced. the opening start point of the 4 carbs.  to the throttle pull?----Ken

LesterPiglet:
I've never heard of such a low idle.
When I do mine I always set the idle a little high, maybe 13 or 14. I've no idea as I've no tacho. I also ignore the numbers on the vacuum guages but get all cylinders as even as possible. After that is done then I turn the idle adjustment screw to achieve a satisfactory idle, still ignoring numbers.
I believe these bikes are meant to run rich at idle so you are best doing a plug chop out on the road.

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