Ignition Issues

i don't use any gauges. yeah looks like a sensor. im checking all cables now and install them new to the coil and ignition.

i replaced all cables with new ones coming from the points to the coils. the only thing that i found that don't really make sense to me are two ground cables that go from from the plate that holds the coils and from one of their screws to ground. are they supposed to be there?

pete greek1 wrote: Could be a vacuum leak in the carb boots, with bike running at lowest idle, spray carb boots with carb cleaner and see if RPMs change
Pete

i tried that right now. as soon i spray in in from the opening to the air filters, it turns off in 2-3 of 4 carbs.

Quote: "as soon i spray in in from the opening to the air filters"Just to clarify...the carb cleaner is to be sprayed on the OUTSIDE of the carb boots/mounts at as low an idle speed possible, indicating a vacuum leak to outside atmosphere...

i did that a month ago already. no change in rpm.

turns out it was the spark plus. they were dead even though only 2 months old. drove it for an hour almost perfectly running, smooth and powerful as hell, then driving most of the time with 10-15% throttle i notice again how it starts hesitating until another 30 min later it ran like crap again. pulled the plugs again and instead of 3 plugs black and one too lean, now the outer plugs are all rich/black and the inner 2 too lean. next step is to rebuild the carbs and get smaller jets, but can it really be already damaged again the sparks? after 2 hours?

What brand of sparkplug? NGK? B8ES is the usual one for the Kz 1000's, not sure about the Kz 750's
Sparkplug Cross Index
www.gadgetjq.com/spark_plug_cross_reference_motorcycle.htm
www.sparkplug-crossreference.com/convert/NGK_PN/B8ES/
www.globaldenso.com/en/products/aftermarket/plug/

Find another brand(like Denso), and try it. I've read that the NGK's made in the US are having quality control problems, but the Japanese NGK's seem to work OK.

Also, replace all 4 of your sparkplug caps. There's a non replaceable 5000 ohm resistor in them, that goes bad from heat & vibration.

i don't use any caps. yes, those were the ones i bought. so i would need to go back to the store and buy 4 more to see if it runs good again or if the carb is stuck again or whatever it is. i have an appointment for next week to rebuild the carbs with a motorcycle dude from the town here. he helped me today to find the problem.

oh you meant the caps that are on the cables. yeah i need those too but they are not the issue right now. but im planning to order those too.

If not already done, would perform the clear tube test to assure fuel levels are within spec.

A fuel level that's too high can cause brand new spark plugs to quickly foul and look sooty.

An engine that performs well for a few miles after installing brand new spark plugs, and then starts skipping/missing (i.e., combustion failure), indicates possibility of too high fuel levels.

Good Fortune!

yes they 2 outer spark plugs are black as hell. i know already they are too rich. so if i lower the float level further, i get it more lean without changing the jets? i am right now taking apart another bank of carbs i bought here from an old bike and play to flip the 2 outer carbs with those ones and make 1 good bank out of 2

element303 wrote: ...2 outer spark plugs are black... they are too rich. so if i lower the float level further, i get it more lean without changing the jets?....

If the fuel level is too high, lowering it to spec level will indeed "get it more lean without changing the jets."

Good Fortune!