KZ900 head on KZ1000?

KZ Riders,
I am looking at possibly putting a 1976 KZ900 head on my 1978 KZ1000 B2 engine. Seems to me that, with the exception of the thinner exhaust mounting studs, this is the same head, valves and cams as the one that comes on the 1978 KZ1000.

Is that right? Or, can anyone out there clue me in to a reason I should not do this-- any differences or incompatibility issues?

Any information and advice greatly appreciated. Thanks.

Yes it will fit without any issues.

Bolt on and go.

That's great-- thanks. Should I use the camshafts/sprockets for the 900 head-- they identical too?

Also, anyone run into any weird issues mounting their KZ1000 exhaust, due to the narrower 900 flange studs?

Camshafts and sprockets are the same from 1973 to 1978. Setup is the same as well.

There are no issues with any of the parts on either 900/1000 heads, all compatible, you just may need washers under the nuts on the exhaust clamps if you don't have 900 clamps.

Thanks to all of you for the information. Here's another question: I have a 1974 Z1 engine. As you know, that is a 903 engine. But, given that the head is the same as the 1000, can I just put the cylinder block from my 1978 1,015cc engine on the Z1 engine?

I understand the transmission may have some differences, but is it also right that the old Z1s were geared more aggressively? If so, could it actually be pretty cool to put the KZ1000 cylinder block on the Z1 bottom end? Or, have I completely lost it? Would this just be a dumb idea?

All thoughts appreciated.

The 1000 has a heavier crank, it has a stronger middle shift fork and the shift return spring is stronger. I have a 903 crank, a KZ 1000 shift fork and shift return spring. They say KHI made the crank heavier to reduce vibration. I always figured the 903 crank would spin a little faster on revup. I have 1015 barrels, Wiseco 10.25/1 pistons, Andrews 1X cams, 33mm Miks among other things. Needless to say she runs great and I ride the piss out of her. :woohoo:
Steve

You can put the 1015 cc cylinders on a Z1 engine. The engines are virtually identical. You will of course have to change the pistons too. Transmissions are also the same, but if you want a little more giddyupgo you could find and install a close ratio tranny. They were made by Kawasaki and sold through dealers. One of my 900's has one. It also had a 1015 kit that I switched back to 903.

Excellent-- much appreciated. Seems like there are a lot of good options. Thanks for all the great information.

Be carefull installing the 1000 block. The liners on it are slightly thicker than the 900 and on some early 900 cases you have to clearance the bores to get the 1000 block on. Test fit it without the pistons, if it slides right on your good but if it hangs up on one of the bores you'll have to address that.