Z2 750 crank (Bossie the Kaw)

  • SWest
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Re: Z2 750 crank (Bossie the Kaw)

18 Sep 2015 15:31
#690747
I had these on the bike when I parked it for 15 years. Cleaned out the tank and ran them until I got new ones. Only issue is they can break if abused.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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  • missionkz
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Re: Z2 750 crank (Bossie the Kaw)

18 Sep 2015 18:20 - 18 Sep 2015 18:21
#690768
Steve and a few of his buddies trying to decide if this is the crank he's been looking for to eliminate any question about the 750 crank possibly
installed previously...



Bruce
1977 KZ1000A1
2016 Triumph T120 Bonneville
Far North East Metro Denver Colorado

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Last edit: 18 Sep 2015 18:21 by missionkz.

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Re: Z2 750 crank (Bossie the Kaw)

18 Sep 2015 18:26
#690769
Must stuck working in the heat... I couldn't stand it myself.

Lookin good man. You are still at stock bore? 1015 Weisco's?
If I knew what I was doing all the time life wouldn't be any fun.

'80 KZ650 E 700cc, dyna ignition and coils, frame up restoration, daily driver
'81 KZ1300 A3 full restoration, custom big bore pistons, 1400cc 6 cylinder super bike
"77 KZ650 B1 - Barn Find, work in progeress
"74 Yamaha DT 400 Enduro

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Re: Z2 750 crank (Bossie the Kaw)

18 Sep 2015 18:57
#690772
The heat just started today. Swamp cooler is acting up, had a box fan this morning while doing my jets. I have lots of low end. Coming home I was behind a plumbing truck. He wouldn't let me by. Instead of dropping down, I just rolled on the throttle and passed him. Can't wait for 500 miles to come. Using the power up and down, changing speeds etc. Has a deeper growl to her.
Yeah, 1015 and 10.25/1 pistons but with the 2.5mm drop, I'll bet it's more like 9-9.5/1. Good enough for me. :whistle:
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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Re: Z2 750 crank (Bossie the Kaw)

18 Sep 2015 18:59
#690773
missionkz wrote: Steve and a few of his buddies trying to decide if this is the crank he's been looking for to eliminate any question about the 750 crank possibly
installed previously...




:woohoo: Now that's a crank. :lol:
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 04:47 - 19 Sep 2015 04:49
#690802
What's the deck height on that :laugh: Some of these marine deisel engines are the size of a block of flats, quite amazing really.


Yeah, 1015 and 10.25/1 pistons but with the 2.5mm drop, I'll bet it's more like 9-9.5/1. Good enough for me

I think about 1 point drop in CR for every 1mm, so down about 2.5 points? 10.25 - 2.50 = 7.75

Is it 8.5: 1 standard? If your head has been skimmed at all that will get some back. If the exhaust valve timing lines are just a bit higher than the gasket face it is one indication that the head has been skimmed.

About 3% power for every point of CR, so I guess you are down less than 10 percent. They do run nice and smooth though you have noticed.




Attachment Compression_Power.gif not found





www.daytona-sensors.com/tech_tuning.html
1980 Gpz550 D1, 1981 GPz550 D1. 1982 GPz750R1. 1983 z1000R R2. all four aces

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 04:54
#690803
I'm going to do a compression test just to see.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 04:55 - 19 Sep 2015 04:55
#690804
A comp test at 500 and at thousand miles will tell you the real numbers. Mines at 165 last check so thinking its right at 10/1 or a hair under.

Whoops too slow. :laugh:
1978 KZ650 b-2
700cc Wiseco kit 10 to 1.
1980 KZ750 cam, ape springs, stock clutch/ Barnett springs.
Vance and Hines Header w/ comp baffle and Ape pods, Dyna S and green coils, copper wires.
29MM smooth bores W/ 17.5 pilots, 0-6s and 117.5 main
16/42 gearing X ring chain and alum rear JT sprocket.
Last edit: 19 Sep 2015 04:55 by KZB2 650.

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 04:59
#690805
Tyrell Corp wrote: What's the deck height on that :laugh: Some of these marine deisel engines are the size of a block of flats, quite amazing really.


Yeah, 1015 and 10.25/1 pistons but with the 2.5mm drop, I'll bet it's more like 9-9.5/1. Good enough for me

I think about 1 point drop in CR for every 1mm, so down about 2.5 points? 10.25 - 2.50 = 7.75

Is it 8.5: 1 standard? If your head has been skimmed at all that will get some back. If the exhaust valve timing lines are just a bit higher than the gasket face it is one indication that the head has been skimmed.

About 3% power for every point of CR, so I guess you are down less than 10 percent. They do run nice and smooth though you have noticed.




Attachment Compression_Power.gif not found





www.daytona-sensors.com/tech_tuning.html

Looking at your chart makes me want to get a 903 crank. On the other hand, I shouldn't have any problems running regular gas. :whistle:
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 06:03
#690815
I guess it's time to close this one out. If anyone has some info on the Z2 750 crank, rod markings, numbers on the crank throws etc. Please post them here. I am confident it is a 750 crank but little is available on identifying markings. I started the Poser thread in response to one members questioning my truthfulness. Rather than stoop down to his level, I did my best to prove what I claimed is true.
In the end, I satisfied the question if nothing more than to myself.
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 06:06
#690816
swest wrote:
missionkz wrote: Steve and a few of his buddies trying to decide if this is the crank he's been looking for to eliminate any question about the 750 crank possibly
installed previously...




:woohoo: Now that's a crank. :lol:
Steve
I went out to the Bar at Lunch and burned a fatty :woohoo:
Livin in "CheektaVegas, NY
Went thru 25 of these in 40 yrs.
I SOLD OUT! THE KAW BARN IS EMPTY.
More room for The Old Girl, Harley 75 FLH Electra Glide,
Old faithful! Points ign. Bendix Orig. carb.
Starts everytime!

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Re: Z2 750 crank (Bossie the Kaw)

19 Sep 2015 06:10
#690820
That stuff makes me stupid. I don't do it anymore. :lol:
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229

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