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i want lower compression
- School Teacher
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thanks guys
1976 kz900 in parts but will be going some day soon
1980 kz1000G1
1976 kz900 parts bike
1979 kz1000 shaftie parts bike
1978 kz1000 33mm smoothies 1075 kit
Troutdale Oregon USA
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- saxjonz
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- KawboyZ
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79 LTD B3
80 LTD B4 1075 kit JE Pistons .410 cam grind, Bassani, 31 keihin CR Specials...
1980 Z1R, 2002 ZRX1200, 2003 ZRX1200
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- bountyhunter
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Well I would go for the gpz head for sure. Maybe a bit more money but it will drop the compression and you will have a better head plus I think they have bigger valves but then again I have been told that you could shave the pistons if they are the wiseco as they have plenty of meat. I don't know the specifics but I would get the gpz head.
First thing I thought of was shaving the top of the pots. Could also mill out the inside of the combustion chamber a shade.
1979 KZ-750 Twin
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- FastKaw1
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You can do two things. Pull the block and add extra base gasket, that will drop
your compression. (Puts the pistons further in the hole)
That is what I would do. Most coast effective.
Or you can pull the pistons and shave the tops off.
If you send the head out to have the combustion chamber reshaped for lower com. IT will only reck a perfectly good head
XENU
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- coppertales
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1982 KZ1100 A2
1982 1100 SPECTRE
1982 1100 SPECTRE
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- bountyhunter
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Pull the head. Are the pistons level with the top of the head?
You can do two things. Pull the block and add extra base gasket, that will drop
your compression. (Puts the pistons further in the hole)
That is what I would do. Most coast effective.
How much effect does that have? I recall the gaskets in my rebuild set were only about .030" thick and probably compress to maybe half that thick under the head torque bearing straight down on the base gasket. I was just wondering how much it would actually drop the compression to add a second gasket.
1979 KZ-750 Twin
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- FastKaw1
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APEgeroge might be a better source.
A stock gasket is .030 Get a copper or alum. around .060 that will put the piston
.030 in the hole. and if I remember correctly 10-12% lower comp.
Make sure you use a good gasket sealer on copper gaskets.
You can stack two .030 to get .060 or any combination.
You wont to worry about valve to piston anymore.
Hope this helps
XENU
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- FastKaw1
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APE JAY
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- School Teacher
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but thanks on the suggestions sounds like i could go either way.
1976 kz900 in parts but will be going some day soon
1980 kz1000G1
1976 kz900 parts bike
1979 kz1000 shaftie parts bike
1978 kz1000 33mm smoothies 1075 kit
Troutdale Oregon USA
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- bountyhunter
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Interesting, I wouldn't have guessed that much.It's bin 30yr. sines I figured this out. boy I hate to say that.
APEgeroge might be a better source.
A stock gasket is .030 Get a copper or alum. around .060 that will put the piston
.030 in the hole. and if I remember correctly 10-12% lower comp.
1979 KZ-750 Twin
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- bountyhunter
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FYI, there is a source for actual octane booster that WORKS because it contains tetraethyl lead. You can easily jack your octane up ten points if you want. It's called:ok i got some 12.5 to 1 pistons(1197) and wanna have premium gas run in it not jet fuel.
Octane Supreme 130
www.batterystuff.com/fuel-treatments/OS6q.html
www.kemcooil.com/specials.php
You can't use it if your bike has a catalytic converter, otherwise OK. I use it on mine.
The stuff they sell at Pep Boys or Kragens only raises it a very small amount because they can't put lead in it. It's pretty useless.
1979 KZ-750 Twin
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- APE Jay
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Jay
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