Adjusting standard carb set-up

[smithymc]

I find the Haynes manual quite confusing on this. It suggests at one point that all you can do is adjust the idle via the throttle stop screw, but then arrows various screws in sketches and photos, which it implies you can adjust.

I have a decent idle and the auto-choke seems to set and then come down in steps which seems ok, but its running a bit rich.

Is there any more adjustment and can anyone point me at the correct bits to twiddle?

Thanks.

Mark

[capriblu]

Assume that it is a Weber DAT/DATR type carb ...?

In which case main means of setting mixture is by adjusting screw on base of carburettor. 

With carb positioned on manifold then adjusting screw runs from rear n/s corner of base of carb and in a n/s to o/s direction - hope that makes sense!

Screw is recessed by several mm and can be opened/closed whilst engine is ticking over using a thin flat bladed screwdriver.  Get tickover somewhere roughly correct using throttle stop and then close screw (clockwise) slowly until you can just start to hear revs drop slightly or first signs of going a bit rough/lumpy. Once you have found this point then open back out by a turn or turn and a half .........    Worth taking screw out completely and checking that rubber o-ring seal around head is in good condition.

[Ammy]

No doubt someone has has a fiddle with the main jets which can be changed in minutes.  There's nothing to  "twiddle" other than the throttle stop screw and the idle screw,  set in the base of the carb.

[smithymc]

Thanks for the replies- yes mine is the DAT/DATR carb, completely standard.

Jets have been out a few times over the past months, as debris from the tank was still turning up occasionally, but seems sorted now.

Mark