Major Problem
- ewolpert
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Re: Major Problem
03 Mar 2015 17:52
Patton, to be honest I didn't hear air escaping from anywhere. I am not sure if I should have used a stethoscope but, by ear I didn't hear anything. I had the regulator on my compressor at 120psi and there was no audible noise. Although to be honest, I did bot stick my head at the crankcase vent. I shall re attempt and listen there.
Eddie
78 KZ650 b2a
78 KZ650 b2a
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Re: Major Problem
03 Mar 2015 18:27
Sounds to me nothing can be done until Friday. I'll say it again, don't jump around. One thing at a time, then move on.
Steve
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
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
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- bountyhunter
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Re: Major Problem
03 Mar 2015 19:36Hence how I don't understand how it can have compression of 80 psi and run quite well. The lower service limit for compression on a 750 twin is 115 PSI (nominal is 150) and the 650 is a higher compression engine.ewolpert wrote: It didn't barely run, it ran quite well.
1979 KZ-750 Twin
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- 650ed
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Re: Major Problem
04 Mar 2015 04:23 - 04 Mar 2015 04:24bountyhunter wrote:Hence how I don't understand how it can have compression of 80 psi and run quite well. The lower service limit for compression on a 750 twin is 115 PSI (nominal is 150) and the 650 is a higher compression engine.ewolpert wrote: It didn't barely run, it ran quite well.
I'm puzzled about the same issue. It's hard to imagine that the compression test is accurate since the bike ran quite well. The standard compression for the KZ650 is 156-185 psi with a service limit of 119 psi. If the compression really is 80 psi I'm very surprised the engine ran quite well, and since the compression is equal across all cylinders it doesn't sound like a valve issue. It sounds more like a faulty compression test. If it was mine I think I would have a second test performed using a different tool. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- PLUMMEN
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Re: Major Problem
04 Mar 2015 04:41
What did you do to sinc the carbs?Try reversing the procedure to see if it makes a difference.

Still recovering,some days are better than others.
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Re: Major Problem
04 Mar 2015 05:51
Hopping around isn't helping ether. On another thread he bought some coils. The wrong ones at that. It's possable that when he does get it running, the compression will come back up. I STILL HAVEN"T SEEN PICS OF THE PLUGS. :whistle:
Steve
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
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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- ewolpert
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Re: Major Problem
04 Mar 2015 07:07I did buy coils, I am certain I did not buy the wrong ones however. Further I have always planned on replacing the coils. In fact I have always planned on replacing the points with electronic ignition. I will post pics of spark plugs soon as you have adequately shamed me on the forum with your posts publicly calling me out for hopping around.opping around isn't helping ether. On another thread he bought some coils. The wrong ones at that. It's possable that when he does get it running, the compression will come back up. I STILL HAVEN"T SEEN PICS OF THE PLUGS. :whistle:
Eddie
78 KZ650 b2a
78 KZ650 b2a
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Re: Major Problem
04 Mar 2015 07:24
Not trying to shame you. I catch myself hopping around too. I did it Sunday working in the box while it was raining. Put in a rotor, put on the cover, noticed the wires in the Reg. needed cleaning, cut back the insulator, cut a wire, SH*T. Didn't even put on my clutch cover damn it. Had I done that, then moved on, I wouldn't have been distracted. It happens to all of us.
One thing at a time.
Steve
One thing at a time.
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
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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- SWest
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Re: Major Problem
04 Mar 2015 07:36
Oh, and I apologize. "Can't talk to you without talking to me". GD
Steve
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
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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- ewolpert
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Re: Major Problem
04 Mar 2015 08:23Not trying to shame you. I catch myself hopping around too. I did it Sunday working in the box while it was raining. Put in a rotor, put on the cover, noticed the wires in the Reg. needed cleaning, cut back the insulator, cut a wire, SH*T. Didn't even put on my clutch cover damn it. Had I done that, then moved on, I wouldn't have been distracted. It happens to all of us.
One thing at a time.
No need to apologize, I have been hopping around. Truth is I have an appointment to take the bike into the CHP for VIN verification next Monday and it is not running. The appointments are a month out and I need it to be running by then so I am trying every thing all at once. Your advice is sound. One thing at a time. Anywho, here are the plugs:
Attachment V__13F7.jpg not found
Attachment V__B76F.jpg not found
Eddie
78 KZ650 b2a
78 KZ650 b2a
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- Patton
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Re: Major Problem
04 Mar 2015 08:57
If an auxiliary fuel supply was used during the sync procedure, perhaps crud has obstructed the float valves.
If the throttle slides were left in too high position after the sync procedure, the "closed" throttle position would be the same as a partly open throttle -- not good -- during the start-up procedure.
Good Fortune!
If the throttle slides were left in too high position after the sync procedure, the "closed" throttle position would be the same as a partly open throttle -- not good -- during the start-up procedure.
Good Fortune!

1973 Z1
KZ900 LTD
KZ900 LTD
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- ewolpert
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Re: Major Problem
04 Mar 2015 09:21
Patton, I have since pulled the carbs off checked all the float valves and jets and bench synched the carbs. I used the fuel tank for fuel. (not on bike of course).
Eddie
78 KZ650 b2a
78 KZ650 b2a
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