bs 34 w/ accel pumps jetting?

Hi all, i have a set of bs34s w/ accel pumps off a 1980 z1000. I am running a modified exhaust. (shorty end piece with baffle) and pods. Jetting recommendations. I know its a 102 main i was thinking 125s? and idk what the pilot jet is i have to look again. Any recommendations would be appreciated.

Admittadly - I've had the most difficulty with the setup you have just described.

125 would be far too much - try 112 - 117 to begin with.
You may not have to change the pilot jets - just turn out the mixture screws about 3 for starters
All depends on your engine and requirements with this application. You will be tuning and fiddling for many hours to come...

Might be best to get a jet kit that has properly tapered needles and a drill to change the slide rate.

The bike will never feel perfectly smooth again without an airbox - sorry, you may think it does after many hours spent tuning - but it wont be.

Good luck!

Those are not BS34's. They would be VM28's.

I would start at 120 - 125 main and you'll have to shim the needles up if they are US model carburetors.

If the needles are the 5CN29 units with no adjustment grooves, shim them up 1mm with a small washer under each one. Pay attention to the order the plastic washers and spring are positioned when you unscrew the slide linkage from the slide.

They probably have a#15 pilot jet and would probably like 17.5 or possibly even #20.

ok thanks everyone i have jets lined up i was just wondering what everyone thought.

I was "ganna" say. I myself have never seen BS34s with a pump. But I do agree that i would not mess with the low speed jets. Do your adjusting with the idle screws. But be careful on some carbs the screws control the fuel and others they control the air. This will determine weather screwing them IN or OUT will richen the mixture. Someone here who actually has that set of carbs would be able to tell you better. I know that on my 78 Z1R the screws adjust airflow. so as you screw them in the mixture gets richer. On the 77 KZ1000 they adjust fuel flow so as you screw them in the mixture gets leaner. I believe that on yours they adjust the airflow because they are on the side. so they will richen the mixture as you screw them in. Meaning, that the screws "fully seated" is full rich idle.