GPZ750A cams in a 79 650 engine.... stock KZ internals?

caffcruiser
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GPZ750A cams in a 79 650 engine.... stock KZ internals?

25 Sep 2006 09:15

#79433

Wondering about the compatibility? If I use the GPz750A cams in my engine, can I keep the stock tensioner, valves, etc?

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apeman
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

25 Sep 2006 09:22

#79437

I believe the GPZ has an electronic tach, so the cams will have no mechanical tach drive gear. Also, the cam chain and gears are different, so you will need to swap in the cam gears from your 650 cams.

Petaluma and Truckee, CA -- member since Jan. 23, 2003;
PREVIOUS KZs: 1980 KZ750H with 108,000 miles; 1980 KZ750E with 28,000 miles; and KZ750H street/cafe project, all sold a few years back.

This is what I do for fun, not for work. It is art, with a little engineering thrown in.

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caffcruiser
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

25 Sep 2006 09:29

#79440

So 650 gears on the 750 camshafts? Sounds good. Thanks!

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letthegoodtimesroll
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

26 Sep 2006 05:26

#79676

What gain will this give? The reason I'm wondering is I have an opportunity to pick up a 750 Spectre engine and am wondering if I could gain from the same change.

1977 KZ650C1, Kerker Header, Dyna ignition and coils, GPZ 750 oil pan and cooler

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The Gringo
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

26 Sep 2006 06:29

#79689

letthegoodtimesroll wrote:

What gain will this give? The reason I'm wondering is I have an opportunity to pick up a 750 Spectre engine and am wondering if I could gain from the same change.

I doubt you would gain much going with cams from a Spectre. They were set up to be a cruiser so the cams would likely be very mild. The GPZ was a performance bike so the cams are designed for higher performance.

Andy
Akron, Ohio
80 Z-1 Classic-Sold
84 GPZ1100
79 KZ 1000 LTD
78 KZ 1000 A2
77 KZ 1000 LTD-Sold
76 KZ 900 The definition of a barn find
76 KZ 900-Sold gone to Denmark
KZ 750 times 3, KZ 650 times 8 Sold 1 down to 7
KZ 550 times 2 80 440LTD-Sold
81 CSR 305-Sold 81 Yamaha XS650 Special

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steell
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

26 Sep 2006 07:09

#79697

Check the part numbers for the Spectre and KZ750E cams at buykawasaki.com, if the part numbers are the same then the Spectre cams would be a a good upgrade for a 650 as the 750E has more lift and duration than the 650 cams, but not as peaky as the GPz750 cams (83-85).

My $0.000002 anyway

KD9JUR

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letthegoodtimesroll
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

26 Sep 2006 15:53

#79832

The Spectre camshafts are the same as the 82 GPZ750 but not the 83 - 85. Would there still be any performance gains with this?

1977 KZ650C1, Kerker Header, Dyna ignition and coils, GPZ 750 oil pan and cooler

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steell
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

26 Sep 2006 20:38

#79916

Over a 650 cam? Yes, and IMHO it would work better than the 83-85 GPz750 cam in a 650, plus it has a tach drive gear.

The 83-85 GPz750 cams give up low and midrange power to gain top end hp, and in my opinion really need at least 9.5:1 compression ratio (10:1 is better).

Post edited by: steell, at: 2006/09/26 23:39

KD9JUR

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caffcruiser
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

27 Sep 2006 04:49

#79950

11:1 calculated compression.

Very little to no low/mid range loss...

Post edited by: caffcruiser, at: 2006/09/27 07:49

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steell
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Re: GPZ750A cams in a 79 650 engine.... stock KZ internals?

27 Sep 2006 15:05

#80092

caffcruiser wrote:

11:1 calculated compression.

Very little to no low/mid range loss...<br><br>Post edited by: caffcruiser, at: 2006/09/27 07:49

That will work

KD9JUR

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