Alfisti, Check this out and see what you think. Skip Patnode 67 Duetto Norfolk, Va.
I discovered another method of adjusting twin Weber Carbs: 1. Make sure the throttle linkage isn't holding the throttles open then back off the idle stop screw (ccw) and make sure the rear carb throttles are going completely closed. 2. Back off the balance screw (ccw) and make sure the front carb throttles are going completely closed. 3. Turn the balance screw (cw) until you can observe the front throttles just starting to open then back it off until they are just closed. This takes a little finesse and a good feel. 4. Turn the idle stop screw in (cw), start the engine and adjust the idle RPM. 5. Adjust the idle mixture screws as far lean (cw) as possible and still maintain a smooth idle. (I screw them in a little at a time until the engine misfires and then back them out 1/8th turn) 6. Adjust the idle screw for about 2000 rpm and observe any roughness. By turning the balance screw very little one way or the other you can eliminate a lot if not all of that roughness. (If you extend the firing order 1 3 4 2 1 3 4 2 you will notice that the engine fires the front two cylinders then the back two. If the carbs aren't both adjusted the same, the different power output can cause roughness). 7. Reset the idle RPM and double check the mixture settings. -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
