What model is it exactly?
That was the kit I wanted. Unfortunately it is not valid for twins (only four)The power curve is very important. There are kits for your bike that will do the job, and were meant for your bike. This site has tons of info on your bike : kz400.com
The Boyer Brandsen kit in the link below is specific to your bike, I think that's the best route to go. You run out of much options for older Japanese motorcycles.:
Boyer Bransden Electronic Ignition Kit Kawasaki Z400 Z650 (331KIT87) | eBayFind many great new & used options and get the best deals for Boyer Bransden Electronic Ignition Kit Kawasaki Z400 Z650 (331KIT87) at the best online prices at eBay! Free shipping for many products!www.ebay.com
It would probably do. But KZ400 parts are 40 years old, hard to get.I don't either. A 440 Kawasaki version of your bike wouldn't work?
In the first case it is a transistorized ignition that only replaces points and condenser (it does not have CDI functions). I used one for a while, it worked fine but doesn't add much (maybe better spark, better starting and better idling). If anyone wants it, I still have it available.Link to points conversion for your bike, (should work, your bike is listed): 1974-1978 KZ400 D ELECTRONIC IGNITION POINTS PLATE ADVANCER TYTRONIC | eBay
Here's a CDI listed for your bike: OEM Kawasaki KZ400 400 CDI Ignition Igniter | eBay
It seems that this would work, you would have to look up the schematics to see how you would wire it.