pilot screw adjustment

If it's broken or just needs tweaked

Moderators: Volker_P, tidd650

User avatar
kbailey
Posts: 27
Joined: Mon Apr 10, 2006 7:43 pm
Location: central Iowa USA

pilot screw adjustment

Postby kbailey » Thu Aug 17, 2006 2:58 pm

So I finally got some time I could work on the bike. I got the carbs swapped out with the ones that I rebuilt. Good news everyone, it runs. and all 4 pipes get hot. though #3 gets a bit hotter.

it is now time for me to fine tune all the adjustments. does anyone have tips or suggestions on how to adjust the pilot screws beyond the procedure in the shop manual?

the procedure calls for doing adjustments looking for an RPM change of 50 rpm. the problem I have now is that the idle is very variable. just sitting there without touching it the idle jumps around by 300 rpm or more. I haven't synched the carbs yet either. which should I do first, or do I have to keep going back and forth until I land on the point that they are perfect? can badly out of synch carbs cause variable idle? can badly adjusted pilot screws cause variable idle?
should I just take it to the dealer and let an experienced tech adjust it? what say you?

User avatar
Ibsen
Posts: 375
Joined: Fri Mar 03, 2006 12:09 pm
Location: Kongsvinger, Norway
Contact:

Postby Ibsen » Thu Aug 17, 2006 4:11 pm

If the idle is very unstable you shoud set all the pilot screws to the same setting first. I belive 1 1/2 turn out from lightly seated should be a good starting point. Then synch the carbs a first time, fine tune the pilot screws, and at last synch the carbs a final time.
Just keep in mind that an unstable idle isn't always caused by the carb adjustment alone. Also the valves, ignition timing and the spark plug gaps has to be properly adjusted. And a small air leak in the intake manifolds can cause an unstable idle too.

User avatar
Vatch
Posts: 232
Joined: Sun Mar 05, 2006 10:26 am
Location: West Virginia, USA

Postby Vatch » Thu Aug 17, 2006 7:15 pm

Yeah, Ibsen summed it up. 8) Throw in a clean set of spark plugs after the carb balancing to see if you need to adjust the pilot screws.
'99 1500 Drifter


Return to “Technical Discussion”

Who is online

Users browsing this forum: No registered users and 41 guests