1978 kz1000a renew and revenge project

november 29 more testing. you can see the results below and here is a description of what i will do next. I will probably adjust the idle screws and pilot jets so that i can offset the 1/10 throttle. The curves kind of point in that direction. most of the WOT pull curves start at 10 or 12 seconds and end at around 2 if you are curious about exactly where the WOT pull starts.

current settings#1-(15),(100)(clip2)(3mm)#2-(12.5),(102.5)(clip3)(3mm)#3-(10),(105)(clip4)(3mm)#4-(10),(105)(clip4)(3mm)recommended changes#1 needs less fuel at idle screw and 1/10. may need 12.5 pilot jet.#2 needs more idle screw and 1/10 fuel#3 maybe less main jet (102.5)#4 needs more fuel at idle screw and 1/10. It seems in a few cases 1/10 is mildly lean but idle is around 14 so I will bump idle down to 12 and maybe that will pull 1/10 down with it. the exact opposite may be true as well. I have a rich idle on 3 and a rich idle at 1/10. all of the AFRs pull right in at a little over 1/8 which leads me to believe I shouldn’t mess with the needles. 1/8 is where the needles take over from the pilot.

if the idle screw is less than 1 turn out or more than 2.25 out I will change the idle jet. It’s getting close! #3 needle valve stick sometimes and throws off afr but its also tuned the best when its not leaking. By the way, this is tuned on marine gas.
Blue is below 12 and red is above 14.7 so yellow and green split at about 13.3 AFR. It’s surprising how stable some of the curves are. By the way, at idle the volumetric efficiency is about 30% or 50 liters per minute at 1500 rpm per cylinder. if you did the calculation it should be are 300 liters per minute theoretically but carbs and worn engines lose efficiency rapidly. I envy you guys that can figure all of this out with plug chops. 3 jets, 1 screw and the transitions from 1 circuit to the next creates allot of plug chopping and you have 4 carbs to do.

Curious, i know this all is just experimentation for you but are all those displays of AFM attained by just cracking the throttle sitting in neutral or on a dyno whereas engine is working under load? Regardless, i Love to experiment too!! So carry on and LEARN! Some things i don't know if you've considered but air-correction sizes and slide-cut are more "variables" you can play with. See i just complicated things, ha.

I like learning.  I do like to experiment. Back in the beginning I did unloaded throttle pulls to get the idle jets rich. Everything since then has been on the road. The same stretch of road, 3rd gear from 3000rpm up, around the corner from my place.

everything is tuned and running ok. I went down to a pilot of 10 and the screw is closed (#1) but it idles and 1/10 throttles well. adjusting the other carbs so that they were richer/leaner to get the 1/10 correct worked. But, I think there is no choice but to replace the seals on the choke plunger on #1. Even running marine gas the rubber rejuvenator only lasted a short while. No harm done because I had fun testing and playing with it. I have an extra set of plungers so I will send them off to be rebuilt.  I could probably ride this around with the jets all over the place but it would be nice if I replace the plunger seals and all the jets move back towards what should be expected. It would tell me the bike is running closer to what is expected .I think the bottom line is that if you have to go to a pilot of 10 and all the other circuits are right you dont really have a choice.