KZ 650 Motor Swap Electrical

I installed a 1978 motor into my 1977 KZ 650, and now I can't figure out the wiring. Has anyone out there performed this swap before? Any help would be appreciated.

The easiest is if you have the 77 motor still and swap over the rotor and outer cover.

Mark

The rotor and outer cover are different, the new motor is lower mileage. I would like to keep the newer charging system.

Then you have to switch some of the harness and switch to a regulator/rectifier unit. I've switched bottom ends and kept my 77 charging system so you'll need some help from someone that's done the swap.

Mark

I did a similar thing essentially, just switching the entire stator setup from a 1978 onto my existing 1977 engine. This involved using the 1978 cover, rotor ond stator, and drilling the 1978 cover to enable the cover to mount to the engine as the dowel positions are different. You don't need to worry about this if you have the whole 1978 engine you're all set there. You can't use your 1977 reg or rectifier with a 1978 engine, so you have the option of getting a 1978 combined rect/reg and wiring it in is what I did, or swapping back your 1977 cover/stator ect onto your 1978 engine and drilling for the different dowell positions.

I haven't made the exact swap you're talking about, but a similar one, installing a 3-phase hi-output stator and corresponding reg/rec in a 79 engine (originally 1-phase).


As Mark and Ron already stated you'll need a new reg/rec if you want to keep the 78 alternator. The 78 stator is a 1-phase permanent magnet setup (2 yellow wires coming from the stator) so you'll need a 1-phase reg/rec.


The 1-phase reg/rec has 5 wires:

- 2 yellow that connect to the yellow stator wires (order doesn't matter).

- 1 brown voltage sense wire that connects to any switched 12V source (switched = no power when ignition is off).

- 1 black or black/yellow that connects to ground.

- 1 white or white/red that is the output and connects to the battery + terminal (preferrably through a fuse).

Note that some reg/recs do not have the brown voltage sense line.


Adapting the new reg/rec to the 77 harness isn't all that difficult once you've removed the old reg and rec, I'm sure we can walk you through it.


Here's a link to the reg/rec you'll need: CLICK

Thanks everyone for all of your replies, they are greatly appreciated. I just got done looking at the stators of both bikes, and have decided to order the regulator rectifier from Z1. Does anyone know where I can order a reproduction wiring harness for a 650?

When looking at the Z1 website, they show different reg/rect for the 1977 and 1978 KZ 650. Since I have a 1978 motor in my 1977 chasis, I'll want to use the 1978 reg/rect?

The 77 and 78 reg/recs are completely different creatures, the 77 is a 3-phase separate rectifier and a separate electromechanical voltage regulator, he 78 is a combined 1-phase reg/rec.

Before purchasing anything, make sure you new engine does indeed have the 78 1-phase stator. Two ways to determine: A 1-phase stator will have 2 yellow wires coming out of the stator (not counting the wire from your neutral switch that runs along the stator wires).

You can also remove the alternator cover and look at the stator - a 1-phase stator will have 12 poles, a 3-phase will have 18.

If you do have the 1-phase stator you will want to use the reg/rec I linked to or similar.

I ordered the reg/rect for a 1978 KZ 650 earlier today from Z1 Enterprises, I should be expecting it in about a week. I will let everyone know when I receive it.

I just received the 1978 reg/rec today from Z1 enterprises. It has four wires coming off of it. The wires are one white, two yellow, and one black. Any help is appreciated.

Looking at your 77 harness you will see a white (or white/red) wire that connects to your old reg and rec and goes to your fuse box and then to the battery + terminal - the white wire (output) from the 78 reg/rec should connect to this wire.

The two yellow wires on your new reg/rec should connect to the two yellow wires coming from the 78 stator, order doesn't matter.

The black wire is ground and should connect to either the frame or a ground wire (black/yellow), I prefer the latter.