no start after new rings - zephyr 550
- TexasKZ
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Re: no start after new rings - zephyr 550
07 Jun 2025 06:54This.Did you try swopping the coil trigger wires left to right (the back firing suggests it's firing out of sequence)
1982 KZ1000 LTD parts donor
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
1981 KZ1000 LTD awaiting resurrection
2000 ZRX1100 not ridden enough
www.kzrider.com/11-projects/620336-anoth...uild-thread?start=24
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Re: no start after new rings - zephyr 550
19 Jun 2025 17:47
Just a quick update. Tried swapping coils - no luck there. I also did a leakdown test. Barely any leakage from any cylinders- maybe 2% with a tiny bit of air coming out of the crankcase. I was hoping to find something obvious...
If there is no leakage that also implies the cam timing is right, correct? I'm not sure what to try now. Maybe I should examine the reluctor wheel as per Daftfrusty's suggestion, though seems a long shot.
If there is no leakage that also implies the cam timing is right, correct? I'm not sure what to try now. Maybe I should examine the reluctor wheel as per Daftfrusty's suggestion, though seems a long shot.
1990 Zephyr zr550 B1
Wiseco 615cc kit
zx550 cams
SPII ignition system
Kerker stainless steel race exhaust with 1.5" competition baffle
K&N Air Filter...
Wiseco 615cc kit
zx550 cams
SPII ignition system
Kerker stainless steel race exhaust with 1.5" competition baffle
K&N Air Filter...
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Re: no start after new rings - zephyr 550
21 Jun 2025 18:53
Man, half a step forward, ten steps back.
Today I opened her up again and reset the cams. I took the cams out, turned one revolution to TDC 1&4 again, and reinstalled the cams, #1 cylinder lobes facing outward. This is in case I had the cams 180 degrees out, though I'm still not sure I understand how that could matter on these machines...
Tried to fire her up with no luck. But then I took off the carbs, sprayed a little starter fluid in each cylinder, and then she'd start fine for a second at a time, pretty consistently. So I was hopeful - maybe it's a fuel/carb issue after all (despite my near religious-levels of carb cleaning, never say never).
But then it's ten steps back. She sounded loud and rattly. I took out the automatic cam chain tensioner and installed a manual one. By the time I got any tension at all on it, the engine would bind when I tried to turn it over by hand. I've installed manual tensioners before, that's very unexpected. I took out the manual tensioner and reinstalled the automatic one. Same thing. I was able turn the engine over once or twice and then it just binds up. I took the valve cover off again and doublechecked timing - everything seems fine - no jumped links, lines all matching up . I went in with a flashlight to try to understand what's happening but didn't see anything obvious. Maybe the cam chain guide is loose or broken? Any other ideas?
I'm pretty dejected - whatever it is I'll need to dig back deep into the engine...and even then I may be right where I started with the bike not starting...
Today I opened her up again and reset the cams. I took the cams out, turned one revolution to TDC 1&4 again, and reinstalled the cams, #1 cylinder lobes facing outward. This is in case I had the cams 180 degrees out, though I'm still not sure I understand how that could matter on these machines...
Tried to fire her up with no luck. But then I took off the carbs, sprayed a little starter fluid in each cylinder, and then she'd start fine for a second at a time, pretty consistently. So I was hopeful - maybe it's a fuel/carb issue after all (despite my near religious-levels of carb cleaning, never say never).
But then it's ten steps back. She sounded loud and rattly. I took out the automatic cam chain tensioner and installed a manual one. By the time I got any tension at all on it, the engine would bind when I tried to turn it over by hand. I've installed manual tensioners before, that's very unexpected. I took out the manual tensioner and reinstalled the automatic one. Same thing. I was able turn the engine over once or twice and then it just binds up. I took the valve cover off again and doublechecked timing - everything seems fine - no jumped links, lines all matching up . I went in with a flashlight to try to understand what's happening but didn't see anything obvious. Maybe the cam chain guide is loose or broken? Any other ideas?
I'm pretty dejected - whatever it is I'll need to dig back deep into the engine...and even then I may be right where I started with the bike not starting...
1990 Zephyr zr550 B1
Wiseco 615cc kit
zx550 cams
SPII ignition system
Kerker stainless steel race exhaust with 1.5" competition baffle
K&N Air Filter...
Wiseco 615cc kit
zx550 cams
SPII ignition system
Kerker stainless steel race exhaust with 1.5" competition baffle
K&N Air Filter...
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Re: no start after new rings - zephyr 550
22 Jun 2025 12:44
When the motor binds, if you wind it backwards does it free off again. What you describe are symptoms of a shell bearing (crank or cam - I’m not familiar with this motor) turning with the crank or cam causing the lock up ????
1982 KZ1000 Ltd
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/filebase-alias?view=download...d-fault-diagnosis&ca
www.kzrider.com/forum/11-projects/617631...-82-begins?start=192
kzrider.com/filebase-alias?view=download...d-fault-diagnosis&ca
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Re: no start after new rings - zephyr 550
23 Jun 2025 08:18No, it doesn't seem to release if I wind it back. However if I loosen the cam chain tensioner a bit I can turn over the engine again. So really seems it's interference with the tensioner and (?)something.When the motor binds, if you wind it backwards does it free off again. What you describe are symptoms of a shell bearing (crank or cam - I’m not familiar with this motor) turning with the crank or cam causing the lock up ????
1990 Zephyr zr550 B1
Wiseco 615cc kit
zx550 cams
SPII ignition system
Kerker stainless steel race exhaust with 1.5" competition baffle
K&N Air Filter...
Wiseco 615cc kit
zx550 cams
SPII ignition system
Kerker stainless steel race exhaust with 1.5" competition baffle
K&N Air Filter...
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- hardrockminer
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Re: no start after new rings - zephyr 550
23 Jun 2025 14:38
I have never timed a 550 engine but I've timed a few 900's and 1000's and a couple of 650's. When finished installing I always rotate the engine carefully to see if it will turn a complete rotation. The problems I've had include the cam chain not on the crank sprocket correctly, two valves touching each other or a valve touching the piston. I should add that whenever I set the cams in place the lobes on #4 exhaust and #4 intake were always pointing towards each other when #1 and #4 piston were at top dead center.
I have several restored bikes along with a 2006 Goldwing with a sidecar. My wife has a 2019 Suzuki DR 650 for on and off road.
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