650 Cylinder Head Swap Question

I did a search but couldn't find anything.:dry:

What I need to know is if a 1979 KZ650 cylinder head will fit on a 1983 KZ650? or if not will any of the valves or other parts fit?

Just got the head in the mail today and looked it over. Everything looks good on it but thought I'd ask the question before I got knee deep in swapping it over.:blink:

Thanks!

IIRC, the sleeves (and cylinder openings in the crankcase) on the KZ650's went' to a larger outer diameter in the early 80's, so the sleeves on that '79 head are probably going to have a bit of play in the cases. :pinch:
I don't know if that would cause any problems (like leaking and/or overheating issues), or even if it can be run like that.
Hopefully someone else that's encountered this has the spec differences between them and will chime in here.

My guess is the head itself won't swap but the head's innards should be o.k. The valve covers will be different as well.

I believe the early 650 has the roller chain and the later 650 has the Hy-Vo set up which also have different chain gears. I can't say for sure but the camchain gear on the top of the older head might have different mounting holes into the different heads/cam chain setups. The newer 650's cam cover has a rubber pad inside of it for chain tension I believe.

You will probably need to swap the sprockets if you are going to change the camshafts. Remember that if you change the valves from head to head you will need to lap the valves and recheck clearances.

Cheers-Colin Firth-Ontario Canada

Well, this should be interesting then. The only thing I got with the 79 head is the head, the entire valve assembly (valves, springs, retainers, shims, valve cups, etc), the spark plugs, and the washers for the head bolts. I don't have the 79 valve cover, timing chain, cams.

So I guess it will be a very close side by side comparison between what I have and what I bought.

Sure would be nice if something could just simply be easy!:blink:

You have the ideal 650 to swap a 750 top end onto, everything would just bolt on and make it into an instant 750.

Really?:woohoo:

Well now I just might have to see if I can find a 750 cylinder head then.

The 83 KZ650 is a 750 with a smaller bore, the 750 cylinder block, pistons, head, and cams will just bolt on. That's why your bike don't have a kickstart