Terrible motor swap idea kz440

  • Wookie58
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Re: Terrible motor swap idea kz440

16 Jan 2026 14:01
#920699
bound wrote:
Can anyone verify that the compression ratio between 1982-1983 (H1-2) and 1984-1986 (A1-3) are the same? If so, that would be sweet!
Have you looked in the filebase at the manuals there ?
1982 KZ1000 Ltd
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/filebase-alias?view=download...d-fault-diagnosis&ca

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  • bound
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Re: Terrible motor swap idea kz440

16 Jan 2026 14:03
#920700
Im in the process of doing that. I verified that my model is 10.0 compression ratio, now I just need to check the 1983 gpz550 compression ratio.
1982 KZ1000M2 CSR
1983 KZ440D5 LTD
1985 GPz 550A2?

Craig

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  • bound
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Re: Terrible motor swap idea kz440

16 Jan 2026 14:07
#920701
They're the same compression ratio which I would think is good, but now i dont know why the 1984-1986 gpz550 has a different part number for the pistons than the 1982-1983 gpz550 
[img
1982 KZ1000M2 CSR
1983 KZ440D5 LTD
1985 GPz 550A2?

Craig

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  • daveo
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Re: Terrible motor swap idea kz440

16 Jan 2026 14:36
#920702
Throw us the part numbers, and/or image links, if any there be

🧐
1982 KZ1100-A2 bike
1984 ZN/ZX1100 motor

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  • bound
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Re: Terrible motor swap idea kz440

16 Jan 2026 14:40
#920704
1984-1986 gpz550:  KAWASAKI OEM PISTONENGINE,STD | 13001-1166

1981-1983 gpz550: KAWASAKI OEM PISTONENGINE,STD | 13001-1127 

I'll see if I can find any quality images of them for you guys
1982 KZ1000M2 CSR
1983 KZ440D5 LTD
1985 GPz 550A2?

Craig

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  • bound
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Re: Terrible motor swap idea kz440

16 Jan 2026 14:55 - 16 Jan 2026 14:59
#920706
Maybe these pictures will help show a difference: 13001-1166 13001-1127 
Clear difference in dome shape. Does anyone see any other differences?
1982 KZ1000M2 CSR
1983 KZ440D5 LTD
1985 GPz 550A2?

Craig
Last edit: 16 Jan 2026 14:59 by bound. Reason: I put in the wrong part number.

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  • Injected
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Re: Terrible motor swap idea kz440

Yesterday 18:33 - Yesterday 18:36
#920712
If one year has a classic dome and the other year a "shoulder" you need to take a look at the two years combustion chamber design on the heads, one might make accommodations for the piston with the shoulder (squish)

The one with the shoulder does not have any flat land at the edge, and that may cause collision in the "wrong" head.
1978 KZ650B2 w 1197cc Z1 engine
1977 KZ650B1 w 750cc Spectre engine
1979 KZ650C3 w 831cc Hot Rod engine
1978 KZ650C2 w 762cc DFI project
1977 KZ650C1 stock restoration project
1978 KZ650B2 modified project
1978 KZ650B2 Injected Drag 831cc
1980 Z1 Custom Frame Drag 1327cc
1981 Z50R Honda tow bike
Last edit: Yesterday 18:36 by Injected. Reason: more info
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Re: Terrible motor swap idea kz440

Yesterday 22:02
#920714
1981-1983 gpz550: 
1984-1986 gpz550: 
1982 KZ1000M2 CSR
1983 KZ440D5 LTD
1985 GPz 550A2?

Craig

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Re: Terrible motor swap idea kz440

Yesterday 00:51
#920719
It might be an optical illusion in the pics but the valves look bigger in the later head ? what is the point of this comparison ? do cruzin image not list pistons for you model year ?
1982 KZ1000 Ltd
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/filebase-alias?view=download...d-fault-diagnosis&ca

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Re: Terrible motor swap idea kz440

Yesterday 12:12
#920725
The valves are the same size, I'm just worried about the dome shape as Injected pointed out. No, cruzin images only shows pistons available for the 1981-1983 gpz550 so I'm trying to figure out if those pistons for the earlier gpz550s will work with my head.
1982 KZ1000M2 CSR
1983 KZ440D5 LTD
1985 GPz 550A2?

Craig

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