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1980 KZ750 E Cold pipe, no compression, opening valve cover
- FaultedGeologist
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Rebuild down to fresh base gasket, all new seals, valves machined, re-shimmed, new carb o-rings after cigarette test, kwik tuned by oldskooler. Cold pipe.
Replaced the carb body in the rack. Same cold pipe.
At shop, re-cleaned and checked carbs, cold pipe. No compression in that cyl but I swear it had comp on rebuild.
Opening the valve cover, my manual didn't survive the divorce. I'm hoping some of the oldskool crew are still here. Nessim, so many others, I'm back!
Clint
Clint
1980 KZ750 LTD H4
FSMaunual: kz.bike-night.com/media/GPz750-full.pdf
Stock except for:
New chain and sprocket (530?).
Dynatek Ignition
Manual tensioner on the way.
Buy JIS screwdrivers.
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- Wookie58
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- FaultedGeologist
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I just measured the valve clearances. All are in spec EXCEPT the Intake of Valve 2, the cold pipe, measuring 0.43mm with a FSM range of 0.08-0.18mm.
I'd like to replace the shim and see before taking the valve body off. All the cylinders and rings were spec, fresh gasket and seal the whole way.
Also, at 1-4 T top TDC at ignition the camshafts seem off by 1 tooth, with Z7EX just angled above the valve body. I can't move them both 1 tooth as they align with the chain links properly. Could it be off by 1 link at the bottom?
Thoughts on leak?
Clint
1980 KZ750 LTD H4
FSMaunual: kz.bike-night.com/media/GPz750-full.pdf
Stock except for:
New chain and sprocket (530?).
Dynatek Ignition
Manual tensioner on the way.
Buy JIS screwdrivers.
Please Log in or Create an account to join the conversation.
- howardhb
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The cylinder head will have to come off I'm afraid...
H.
'81 GPz 550 D1
'81 GPz 1100 B1 ELR "Tribute" www.kzrider.com/our-forum/11-projects/61...-elr-tribute?start=0
'82 Yamaha YB100 Fizzie
'79 Suzuki GT200 X5 TWO STROKE TWIN - SMOKER!
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- Wookie58
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- FaultedGeologist
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z1parts.net/13mm-valve-shim-kit-4pcs-of-...n-0-05mm-increments/
ISO shims posted, 13mm diameter, 2.6mm-3.1mm
It could just be sloppy work at the machine shop, or something seating better. I can see how debris down there would cause a little lift and gap, but I would think there would be some mechanical feeling or resistance as I turn the 17mm driveshaft nut. Hmmm...
Clint
1980 KZ750 LTD H4
FSMaunual: kz.bike-night.com/media/GPz750-full.pdf
Stock except for:
New chain and sprocket (530?).
Dynatek Ignition
Manual tensioner on the way.
Buy JIS screwdrivers.
Please Log in or Create an account to join the conversation.
- FaultedGeologist
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Cylinder likely never fired. Checking leakdown, then pressing valve out to check it. Totally makes sense that if it was off by 0.2-0.3mm it would not prevent the valve from opening; would just be a slappy loud valve. wrote: That clearance of 0.43mm would seem to indicate that the valve is either bent, or, something is stuck in between the head of the valve and it's seat, preventing it from closing.
The cylinder head will have to come off I'm afraid...
H.
Clint
1980 KZ750 LTD H4
FSMaunual: kz.bike-night.com/media/GPz750-full.pdf
Stock except for:
New chain and sprocket (530?).
Dynatek Ignition
Manual tensioner on the way.
Buy JIS screwdrivers.
Please Log in or Create an account to join the conversation.
- howardhb
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'81 GPz 550 D1
'81 GPz 1100 B1 ELR "Tribute" www.kzrider.com/our-forum/11-projects/61...-elr-tribute?start=0
'82 Yamaha YB100 Fizzie
'79 Suzuki GT200 X5 TWO STROKE TWIN - SMOKER!
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- H1Vindicator
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not sure what that means. but the 750turbo site has a good manual. the one here on kzr is a crummy version but that would be better than nothing.
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- FaultedGeologist
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Pic 1: kwik carb holder setup w string.
Pic 2: butterfly look really close to same, this was after rebuildi g the carbs with a new body for pipe 2 from left.
I have not done further leakdown using the air method. Following another thread with the same issue.
Clint
1980 KZ750 LTD H4
FSMaunual: kz.bike-night.com/media/GPz750-full.pdf
Stock except for:
New chain and sprocket (530?).
Dynatek Ignition
Manual tensioner on the way.
Buy JIS screwdrivers.
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- Injected
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The main culprit was a malfunctioning cam chain tensioner, that big ugly double wedge job. I bent two valves because the cam chain had slop in it when first fired. No compression in one cylinder, one intake valve bent .002" and one exhaust valve bent .004" both straightened on lathe then reground.
Did you replace the cam chain with a new one?
If you don't then the cams will never line up at TDC like the manual shows, always up or down from the gasket surface. I ended up setting my cams up by using a dial indicator on the tappet to tell me when the valves were closed! I have since ditched the giant auto tensioner for a manual unit.
This spring I am going to slot my cam sprockets so I can better set the cams up, this is one way around a slightly elongated chain (the chain was within FSM limits)
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- FaultedGeologist
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Clint
1980 KZ750 LTD H4
FSMaunual: kz.bike-night.com/media/GPz750-full.pdf
Stock except for:
New chain and sprocket (530?).
Dynatek Ignition
Manual tensioner on the way.
Buy JIS screwdrivers.
Please Log in or Create an account to join the conversation.