Basic carb setup

[Z1B Alan]

Had my carbs ultrasonicly cleaned [thanks Ginger Bear] and have now reasembled them ready for refit. Whilst setting up the slide heights I have noticed that if I set them all at 0.7mm from the notch to the venturi when the slides lift up to the fully open position two slides clear the venturi before the others. If I set them so they all clear the venturies at exactly the same time when they are in the shut position you can see that no2 is lowwer than the rest. I know if the no2 slide is adjusted too much you can lift the other three as when the slide bottoms out it rotates the common shaft and lifts the others this is definatley not the issue. I would like to know which set up is the most important level at top or bottom my idea is at smaller throttle positions any differance would be critical as against full throttle where the percentage differance would be less.
any ideas welcome. I would just add there is no chance any parts could have become mixed between each other as they were all kept in sealed metal tins.

[Garn 1]

Alan, you are describing an impossible situation. I would think your bottom position (0.7mm) is not correct. Assuming you have the carbs off the bike, and you are viewing from the engine side, try two or three a 3/16"ball bearings and see if they all move down the throat simultaneously, then check the top to see if the slides disappear together.
RegardZ.

[zed1015]

set the slide levels initially with throttle shut using either Garns ball bearing method or the plain shanks of four 2 or 3mm hss drill bits etc and adjust for tickover accordingly once running, this should be good enough for fairly smooth running but if you have them vacuum balanced you may find that the slides will sit at slightly different heights due to the pumping efficiency of each individual cylinder.

[GEZ635]

I agree with zed1015 with regards to using a 2 - 3 mm drill bit.Adjust each carb until each slide comes into contact with the shank of the drill bit and offers a little resistance. Once all 4 are the same you should have a basic setup which will allow you to balance them correctly, although you may find they are pretty near as they are! I have just checked a perfect running set of z1b carbs and I can just get a 3mm drill under each slide with a little resistance.

[GEZ635]

I agree with zed1015 with regards to using a 2 - 3 mm drill bit.Adjust each carb until each slide comes into contact with the shank of the drill bit and offers a little resistance. Once all 4 are the same you should have a basic setup which will allow you to balance them correctly, although you may find they are pretty near as they are! I have just checked a perfect running set of z1b carbs and I can just get a 3mm drill under each slide with a little resistance.

[ade woollams]

whats the cost of ultrasonic cleaning on carbs and what gets cleaned

[Rich]

" my idea is at smaller throttle positions any differance would be critical as against full throttle where the percentage differance would be less. "

Set the slides for slow running as you say when open fully slide height is not critical as long as they all clear the venturi.

[ROZZER]

Looks like getting 4 off 3mm drill bits is the way to go our kid (did same on Daves Bonneville and it was spot on from the off). The 0.7mm you are checking is from the airbox side, engine side has bigger cut out on slide hence the 3mm drill bit will fit.
Gonna order a Carbtune 2 to replace my mercury gauges, so we can do final set up then. Just give it a run with initial set up, see if starting has improved after the ultrasonic clean' if not then its new refurb kits inc needle jets mucker.