GPZ1100B1 bottom end and A2 top end, help needed

Hi guys
I am building up a 80's superbike replica based on my GPZ1100B1.
I have the original B1 engine and an A2 engine as well.
Here's where it gets complicated. I want to basically keep the cases off my B1 so the frame and engine No's match and use the A2 internals (the A2's top end is sooooo much better) and it has the 6 spring clutch etc. Has anyone out there done this?
Alternately I will just use the A2 head. who makes good pistons that will best suit the A2 head? don't really want to go much past 10.5:1.
Finally what's the opinion on RS34 Vs RS36 carbs? I'm definately looking for performance but not so I can't easily ride it on the street.
Started out thinking I was just restoring it but I am just so much past that now, weird eh. Now I'm pretty much obsessed with it. At least it makes me happy.

Based on what I have read, the A2 crank etc should fit in the B1 cases.

A2 has 17mm wrist pins, and the B1 has 18mm wrist pins, and I haven't seen any B1 pistons for the A2 head. The B1 head is much better than the A2 head so it would be unusual for someone to use an A2 head on a B1.

If you use the A2 crank, rods, pistons, and head, in the B1 cases, you should be ok.

My primary interest is the 750 twins and fours, so I suggest not taking any of the above as gospel, one of the 1100 guy's will probably be along soon to confirm or deny

i am not up on the gpz's . could u please educate me on what the a and b models are? are we talking 82 j version compared to 84 gpz?

81 kz1100b1 injector ports in head, flapper air flow meter 17mm wrist pin
82 kz1100b2 injectors mount with throttle bodies
17mm wrist pin

have never seen 83 or 84 gpz1100

Duck wrote:

81 kz1100b1 injector ports in head, flapper air flow meter 17mm wrist pin
82 kz1100b2 injectors mount with throttle bodies
17mm wrist pin

have never seen 83 or 84 gpz1100

I just checked kawasaki.com and you are absolutely correct, the B1 and B2 used 17mm wrist pins, the B3 and B4 (83 and 84)had the 18mm wrist pins.

I was thinking the B2 was the 83 model, but it's the 82. So everything from the A1 (Kz1000 Shaft) motor should fit in the B2 (except possibly the trans output shaft)

A1 and B2 heads are probably the same.

Thanks for the comments so far. I should have made it a little clearer.
The Gpz1100B1-B2 is the 81-82 models with the 17mm wrist pins.
The Gpz1100A1-A2 is the 83-84 uni-track models. The same engine is in the ZX1100 and the 84 ELR, they all have the 18mm wrist pins.
I forgot they use those A and B designations in the KZ1100 shaft models, so sorry about that.
As far as I can tell, if I fitted the Gpz1100A2 head to my Gpz1100B1 bottom end using the B1 pistons with the 17mm pins I would have a good head but with fairly low compression.
So I figure I need to fit the Gpz1100A2 crank with rods co I have the 18mm wrist pins. As the A2 head is a Hemi type and the A2 pistons have a much deeper cut-out for the valves.
Does anyone know the cam specs (lift and duration) on the Gpz1100A2 and if they are the best choice?

Damned GPz models!!

I forgot they changed the prefix on the GPz mono shock models to ZX instead of KZ :blush:

81 GPz1100 = KZ1100B1
82 GPz1100 = KZ1100B2
83 GPz1100 = ZX1100A1
84 GPz1100 = ZX1100A2
95 GPz1100 = ZX1100E1
96 GPz1100 = ZX1100E2

That is from kawasaki.com, so it's probably right

According to MegaCycle, the GPz1100 cams have .354 lift and 238 duration, I think that's for the 83-84 cams, but I don't know for sure. I'll look for my manual to see what it says.

My manual covers the 83 KZ1000 but not the 83 1100 (it does cover the 82 1100 though), and it doesn't give the valve lift, plus it lists the duration at 0 lift, not the normal .040".
So, no help there.

I just checked another site that I frequent, and the general consensus there is that the 83-84 GPz1100 cams have .375" lift.