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'77 Kz650c Potential Valve Issues
- rage_rides
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Attachment CAM00118.jpg not found
I've got a 1977 KZ650C chop. It ran fast and loud before I started having some issues a few weeks ago. One day I started it up and after a brief warm up and ride it felt like it was running poorly and wouldn't stay running at an idle. I parked it at home and let it sit. It was just after dark and while trying to get it to run again I realized it wasn't firing correctly on the number 3 cylinder. The exhaust tube coming from number 3 wasn't cold, however, it was searing hot. If I gave it some throttle (while running) it would smell like hot and the pipe itself started glowing a dull orange. I immediately turned the bike off. I cleaned the carbs, jets, float needles, made sure floats were adjusted correctly, etc. The problem has persisted though and I won't let the bike run for more than needed to try out little fixes.
Does this sound like a stuck valve on the exhaust side of cylinder 3? If not, what should I look at next? If it is, should I remove the cylinder heads and start there? I have the Clymer manual and have taken the bike apart a few times, but I don't want to get into the block before I get a second opinion.
I appreciate any help.
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- !Seymore
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C.
83' KZ750-F1 LTD [clymers] (Kay)
82' KZ1100-D1 Specter (another project)
78' KZ650-B2a (J&H, A Project)
91' KZ1000-P (P = parts)
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- Nessism
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- rage_rides
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- Patton
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The advancer might be rusted and stuck in position, or the pivots might simply need lubing.
The advancer isn't supposed to look like this:
Where lubing is desired, may sometimes reach the pivots through the timing inspection window (without needing to remove the points plate in order to gain full access to the entire advancer).
Good Fortune!
1973 Z1
KZ900 LTD
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- !Seymore
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rage_rides wrote: I haven't run a compression check. Should I? And what would poor compression indicate for the situation? And I haven't done a valve adjustment since I've owned the bike, I should probably take a look at that.
Could mean a valve adjustment or other compression leak problems... let us know what you have here, before tearing into the engine. Helps to diag the problem before tearing in and not knowing some baseline.
C.
83' KZ750-F1 LTD [clymers] (Kay)
82' KZ1100-D1 Specter (another project)
78' KZ650-B2a (J&H, A Project)
91' KZ1000-P (P = parts)
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- SWest
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rage_rides wrote: Hey, this is my first post. This is a rad community and I'm stoked to be a part of it!
Attachment CAM00118.jpg not found
I've got a 1977 KZ650C chop. It ran fast and loud before I started having some issues a few weeks ago. One day I started it up and after a brief warm up and ride it felt like it was running poorly and wouldn't stay running at an idle. I parked it at home and let it sit. It was just after dark and while trying to get it to run again I realized it wasn't firing correctly on the number 3 cylinder. The exhaust tube coming from number 3 wasn't cold, however, it was searing hot. If I gave it some throttle (while running) it would smell like hot and the pipe itself started glowing a dull orange. I immediately turned the bike off. I cleaned the carbs, jets, float needles, made sure floats were adjusted correctly, etc. The problem has persisted though and I won't let the bike run for more than needed to try out little fixes.
Does this sound like a stuck valve on the exhaust side of cylinder 3? If not, what should I look at next? If it is, should I remove the cylinder heads and start there? I have the Clymer manual and have taken the bike apart a few times, but I don't want to get into the block before I get a second opinion.
I appreciate any help.
WTF is that?
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- PLUMMEN
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Still recovering,some days are better than others.
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- Patton
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Good Fortune!
1973 Z1
KZ900 LTD
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- bountyhunter
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That the valve is not fully closing or is not seating well.rage_rides wrote: I haven't run a compression check. Should I? And what would poor compression indicate for the situation?.
1979 KZ-750 Twin
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- rage_rides
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- !Seymore
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bountyhunter wrote:
That the valve is not fully closing or is not seating well.rage_rides wrote: I haven't run a compression check. Should I? And what would poor compression indicate for the situation?.
...or rings that are no longer sealing. But a leakdown test helps, in this regard.
Yes RR, please do keep us posted with what you discover.
C.
83' KZ750-F1 LTD [clymers] (Kay)
82' KZ1100-D1 Specter (another project)
78' KZ650-B2a (J&H, A Project)
91' KZ1000-P (P = parts)
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