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Here is a tough one!
- zombiescustoms
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NOTHING! the bores are spotless, the pistons are clean the plugs perfectly light brown, no odd deposits of any sort. but running down the road it looked as though I was spraying for west nile! the bike had 140psi in all 4 cyls, the only odd thing I found was there was no O ring where the timing chain galley is, just some hi temp black rtv. so can I assume the valve guides are that shot?? Strangely enough the bike only smoked when hot, and did not have any blow by out the breather and did not smoke while decelerating. I have been around engines all my life and this one has got me stumped!!
What I did find out is the P.O. lied to my about the work that had "been done"
he said it was a 1150cc
when I said do you mean 1105? he says yes and it had bug cams and port work done, the reality is it's a 1075cc but has 12:1 comp>>> hence why it wont run on pump gas!!! Stock cams and some port work that looked like my 3yo daughter did!
So what now? need to lower compression and find out where the oil is comming from
any ideas out there???
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- timebomb33
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1973 z1 2-1974z1-a,2-1975z1-b dragbikes1015cc+1393cc, 1977kz1000,1978kz1000,1981kz1000j, 1997 zx-11, 2000 z12r,1428turbo nitrous pro-mod and a shit load of parts thats all for now leader sask.,CANADA
I THINK MY POWERBAND BROKE
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- zombiescustoms
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I think I'm just going to look for a J head and leave the rest alone, according to what I have found using a J head will get me down to around 10:1 which is where I need to be to run pump gas.
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- wiredgeorge
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wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
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- bill_wilcox100
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Could be caused by an excessive exhaust valve stem or valve guide gap or just needs a new rubber valve guide seal and spring.
Best of success.
1977 KZ650-B1 (Stock)
Upgrades:
- Dyna S Electronic Ignition (DS2-2)
- Dyna 3 Ohm Coils (DC1-1)
- Coil Repowering Mod
- Progressive Springs Front & Rear
- Saddlemen Seat Cover
- New Metallic Red Re-Paint & Repro Badges.
Montreal, Canada
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- zombiescustoms
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I am sure you know that a J motor uses a hyvo cam chain. You need to buy an idler assembly that will fit the J head that uses the bicycle cam chain. APE sells them as well as a jig for drilling the J head to install the new idler assembly I think.
Yes I did know that , but one question is because of the chain differences, can you use the j head cams with kz gears or can you put kz cams/gears in a j head??
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- StreetfighterKz
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Later, Doug
1978 z1000 Streetfighter
1976 z900 Stripfighter (work in progress)
1983 Gpz750 Resto-Mod
1989 Vmax
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- 531blackbanshee
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skiatook,oklahoma 1980 z1r,1978 kz 1000 z1r x 3,
1976 kz 900 x 3
i make what i can,and save the rest!
billybiltit.blogspot.com/
www.kzrider.com/forum/5-chassis/325862-triple-tree-custom-work
kzrider.com/forum/5-chassis/294594-frame-bracing?limitstart=0
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- zombiescustoms
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- StreetfighterKz
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Correct, no smoke untill warm, running down the road at speed, which in my eyes rules out guides???
I would think. But the other thing that came to mind is you only have 140psi with 12:1 compression? With stock cams you won't have a lot of overlap so the cams won't affect compression that much. I'm guessing rings even though the bores look fine. Maybe they lost tension from too much heat? Can you do a leak down? That might tell you something.
Later, Doug
1978 z1000 Streetfighter
1976 z900 Stripfighter (work in progress)
1983 Gpz750 Resto-Mod
1989 Vmax
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- zombiescustoms
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- StreetfighterKz
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What would you think the PSI should be with 12:1??
Well atmospheric pressure is 14.7psi so 14.7psi x 12= 176.4psi. That should be your theroetical pressure. So if you measure 140psi you have a 20% loss of compression somewhere. Granted this is all ideal but gives you a general idea.
Later, Doug
1978 z1000 Streetfighter
1976 z900 Stripfighter (work in progress)
1983 Gpz750 Resto-Mod
1989 Vmax
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