Throtle Slide Adjustment

[angeleddie]

Hello Z poeple

I am aware that the throttle slides on my 26mm carbs (Z1000a1) should be set to .7 The question I have is at what position should the throttle stop screw be at prior to making the adjustment?
The carbs are currently off the bike.

Any advice would be appreciatted

Thanks

Angeleddie

[Pigford]

Not 100% sure what you are asking......


Assume you're going to balance the carbs by setting the slides at 0.7mm open? Using a drill bit or something?????

Any size drill bits ok.... 0.5mm - 5.0mm would do, as long as all same across the 4 carbs. Throttle stop should be wound open (unscrewed a bit) so its not doing anything whilst setting carbs up

[DogsbolloxofZ1B]

On a z1 the distance between the top of the bracket and underside of the adjuster thumwheel is 10mm, I think the others are basically the same. Trick is to decide which remains your master (Normally No.4) and leave that one alone otherwise you end-up going around in circles to get them all spot-on.

[BShaw]

if you need to know more Eddie, I am sure that one of us will do our best to tell you how. It would be easier to tell you over the phone, to be honest, well for me it would any way, as it's a 10 min job that would take me 15 Min's to type up.

[Garn 1]

AngelEddie, this is a difficult question to ask, and answer. However, it is extremely important, to get it right.

I have spent much time getting the slides so they all move up at the same time (same datum position.. using number four carb slide as the base). The trouble is when you mount carbs on the head, you find you have limited or no adjustment for idle. I've given up using the 0.7mm wire and drill bits and use three or four 3/16 inch balls.

I do not know a simple answer to set this up, except to give yourself some (slight) adjustment when your slides are just about to lift from the bottom.

RegardZ.

[Steve Cooke]

You set it just short of midway prior to setting the slide heights.

[DogsbolloxofZ1B]

You should set the slide heights using a 0.025" wire and the height you are nominally setting is the notch height in relation the the arc of the carb body. You're not only synchronising the slides but also setting the airflow, hence the vacuum, across the needle and jet at idle. setting it at any other point defeats this second requirement..

[Garn 1]

Dogsbollox, the setting of the slides with a 0.7 mm, 0.025", a 0.5mm drill- bit or a 3/16" ball are all phyical dimensions to have the slides equal, without measuring vacuum. This is only a prelimanary way to set up, prior to having a vacuum gauge or manometer tune, however, it does establish an accurate position to start from and mostly little or no other adjustment is required.

It is the setting of this position, that allows us to know that we are in the "ball-park", before the final vacuum tune, with regards to the range of idle and full throttle. This I believe, is what this question is about!
Other than this measuring technique, I do not know of a way to get the vacuum close to correct, while carbs are off the head! It is always assumed that needles would always be set in the same notch.

RegardZ.

[angeleddie]

Hello Guys,

Thanks for all the advice. It has been very helpful. I seem to have them set now. I guess I wont know until I try to start it which I guess will be in a few mths once I have done everything else, which seems endless!!

Cheers

Angeleddie

[Steve Cooke]

I agree with Garn1, the setting of the slides at this stage is purely to give a datum and nothing more, I understood the request to be for the position of the throttle stop screw prior to this initial setting of the slides.
Furthermore I don't think it is good practice to use a wire for setting the height as the return spring pressure on the slide against such a small wire can make an impression in the thin bottom rim of the slides, you can often see the result of this by the physical marks in the lower rim of the slides when this has been done, the ball bearings are the better option albeit a bit more fiddly.

[DogsbolloxofZ1B]

I don't disagree, but either in this post or another similar someone said use an 8mm drill so set the heights! yes this sets the height but anything larger than a 3/16 drill begins to touch the slide either side of the notch, the notch is what must be set initially and if you do it this way your adjustments with vac gauges will be minimal if indeed required at all.