1978 kz1000a renew and revenge project

  • Wookie58
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Re: 1978 kz1000a renew and revenge project

Yesterday 07:12
#918063
There are a lot of guys on here like Zed1015 and "injected" with much more experience that me with these carbs that can probably better advise on the finer points of set up (I do know that "snapping" the throttle open will cause a momentary learn condition as the jets try and catch up with the sudden increase in air speed unless you are using carbs with accelerator pumps)

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  • bry195
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Re: 1978 kz1000a renew and revenge project

Yesterday 10:11 - Yesterday 10:13
#918067
Maybe they will chime in. 

Im intentionally snapping the throttle to create a worst case. Rolling on throttle still has a minor problem but it’s reasonable. If snapping the throttle is beyond the capability of these carbs then that would be important information and would change the sacrifices I make in solving each problem. I guess an accelerator pump is kind of the perfect solution that they added later. Thank you, very much appreciated.
Last edit: Yesterday 10:13 by bry195.
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Re: 1978 kz1000a renew and revenge project

Today 20:04
#918078
I read thru this thread and one sentence stood out, "The concept is to have the bike idle at 14.7 for efficiency and enrichen to 12 for power".

Trying to get a air cooled engine to idle at 14.7 is way too lean, and not recommended. There really is no way to accomplish this especially with fixed jetting on +45 year old original equipment.

Snapping the throttle without any extra fuel input (accelerator pump) is just going to create all kinds of lag/lean conditions that are typical of these old round slide carbs. These carbs were always a compromise, they have enough performance for a stock engine, but are not a "high performance" part.

The accelerator pump carbs that Mikuni put out back then were mainly focused on fixing lean emissions jet settings for the USA market. Those pumper carbs helped transitioning between the "circuits", but again they were never intended to be a high performing carb set.

I have found that the newer CVK carbs run "almost" as good as fuel injection on these old air cooled engines. This is the cheapest option without slapping on a set of RS34 flat slides (which work well)

The best way to set up a stock engine combination is with the stock air box, and stock jetting as engineered by Kawasaki. If you want to work with the pipe and even the pods that's fine, but the best way to get it to run correctly is to go back to stock jetting and run air correction jets (for the pod filters)
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