1980 KZ1000 B4 Ignition

well be that way... I'm taking my toys and going home... :woohoo:

Well the parts arrived and I went to work on the new setup. Unfortunately I was in quarantine for two weeks after a visit to the USA, so I wasn't able to test out the bike until yesterday. While the bike was down I also changed the rear sprocket from 35 to 33 teeth, which is the standard for this bike. I had mistakenly believed it was 35, like a Z1.

The parts removed are all shown in Mikaw's photo, but for clarity, I removed the standard pickup and magnet, the exciter, the coils and the ballast resistor. Everything was original to the bike except the 2 ohm coils, which I had purchased from Dyna when I rebuilt the bike a couple of years ago.

The parts installed included a new Dyna pickup and magnet, and two new green (3 ohm) coils. I had to make a minor mod to the wiring, as this bike uses the Wired George coil power modification. I had to put a double female connector on the power wire coming from the relay to plug into the coils to replace the wires that originally came from the exciter/ballast resistor.

I took the bike out for about 140 km ride yesterday. I filled it up with gas because I was only getting about 120 km on a tank before the change. I thought it was because of the carbs, and have been fiddling with them but now I believe it was because of the ignition. I have to say it's never run so smooth. The intermittent dropping of a cylinder or two is gone. The lower gear ratio has the bike running about 105 kph at 4,000 rpm. I was still on main tank after 140 km. All is good!

My only regret is that I never actually discovered what was causing the coils to drop out. It was something between the pickup and the exciter, so those parts are no longer reliable and went into the garbage. The coils themselves tested correctly. Plug wires were probably all good but they are now replaced.


The Wired George Coil Power Mod

Good to hear...

I wasn’t aware the B1to B4 used a 33 tooth rear sprocket. I put a new one on 20 years ago but just figured I went to 33 for cruising. But know I know I just replaced the original.

I’m at 3,500 at 55 mph.

I have two different OEM coils for my KZ440 which both test well within spec electrically, but both have issues throwing a good spark. One of them is also leaking dielectric oil. When you're dealing with the 35-40 kV that these coils can generate, it's not uncommon for problems to become apparent which were hidden when testing with a 9V multimeter battery. The very angry pixies find more creative paths through the coils which the calmer angry pixies from your multimeter can't take.