Carbs Help required - 10 miles north of York

[LTD Project]

So I have rebuilt my carbs and replaced old coils with green dynas and dyna ignition leads.

She now starts like she never did before ie on the button and revs keenly but i cannot get her down to an idle even with the idle screw fully backed out. she persists at idling somewhere between 2-3K. Have tried to set the air screws with colourtune and have tried to balance with Morgan carbtune, these improved the situation a bit but did not remove it.

Now I know that I have done something stupid but if I were to be honest I probably have got to the end of my knowledge/experience...

Should there be a kind soul ( read well experienced and knowledgeable at setting carbs up ) out there that might be able to come and lend a hand in the next couple of weeks I sure could do with it. Tea, sandwiches and tunnocks caramels or a beer or two are all on offer should anyone be so kind.

[chrisu]

sounds like the slides are too high

you need to drop them down to get it to drop the revs then you can balance the carbs.

what is the gap between the slide and the carb body with the throttle shut ?

have you backed off the tickover adjuster all the way ?

[Bruce Sexton]

I had a similar problem on my Z1a when I had the carbs stripped and cleaned.
On the carb pully where the cables attach there is a pin with a crosshead groove and a nut, you will see that the pin is off center and can be adjusted by undoing the lock nut. I undone the nut and adjusted the position of the pin to allow the throttle slides to drop lower and this in turn dropped the reves and allowed the throttle adjustment screw to work as it should.
I'm not sure if this is the correct method but it worked on mine and has be fine since.

All should become clear if you look.

Bruce

[LTD Project]

Guys thanks for your swift responses.

Chrisu: Yes have backed off the tickover adjuster all the way.

Bruce: I did not notice the crosshead pin you mention when rebuilding them so will go have another look.

Before fitting the carbs to the bike I manually set the throttle slides to a 1 mm gap and carefully checked the float heights. Thankfully only one was out as it is a boring old job.

Dontcha just hate it when she gets the upper hand.... the bike that is.

[GPRD]

I'm no carb expert, but I've taken mine apart a few times, when putting them back together, where the tickover screw is, there's supposed to be a gap, 2mm springs to mind, so that you can back it off if required.
Also, I didn't think there was supposed to be any gap bewtween the bottom of the slides and the carb body when normal.

[Garn 1]

As Chrisu suggests, you will have to drop the slides down, evidently 1 mm was too big a gap. I think they recommend 0.7mm, so its pretty critical.
The rotten part is you have to see the gap from the engine side and ensure you can still adjust with the thimble to possibly no gap, as GpRD says.
Making them all the same gap tends to go a long way towards balancing the carbs!
RegardZ.

[Steve Cooke]

Double check the adjuster screw position as that has to be set correctly before the cable adjusters are set to ensure that there is adjustment either way after the cables are set.