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Discussion Starter · #1 ·
Hello group, Im reviving my old CB400 Hondamatic. at this point she's running good, have to kick start it, I can only get the starter to engage if I run a groung lead the the Grn / Rd wire at the starter solenoid, but then the Neutral light is
always on, and the bike will start in gear. Im wondering if the issue could be with the Change Relay, I honestly not sure
how it even works. Any input is appreciated.
Thanks and Happy New Year
Keith
 

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Your change switch relay is bad. When the motor is in neutral the change switch is off and the relay is on you should have a neutral light. The starter circuit is grounded thru the change switch relay. When the motor is put in gear the change switch is on and the change switch relay is off and the starter circuit is no longer grounded. This is to keep you from starting the motor when it is in gear. .When you jumped it the relay is bypassed.
The change switch also effects the idle circuit and the side stand switch. You should replace it. I have seen used ones on the net for as low as $10.00

Bill H
 

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Discussion Starter · #3 ·
Your change switch relay is bad. When the motor is in neutral the change switch is off and the relay is on you should have a neutral light. The starter circuit is grounded thru the change switch relay. When the motor is put in gear the change switch is on and the change switch relay is off and the starter circuit is no longer grounded. This is to keep you from starting the motor when it is in gear. .When you jumped it the relay is bypassed.
The change switch also effects the idle circuit and the side stand switch. You should replace it. I have seen used ones on the net for as low as $10.00

Bill H
Thank you Bill for the speedy and I believe very accurate reply.. I was suspecting that but quite honestly have never
had issues with one of the Hondamatics, so therefor no experience with them.
Have a Great New Year,
Keith
 

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Discussion Starter · #4 ·
Thank you Bill for the speedy and I believe very accurate reply.. I was suspecting that but quite honestly have never
had issues with one of the Hondamatics, so therefor no experience with them.
Have a Great New Year,
Keith
Good Morning Bill,
Well you were correct, I found a used change relay on Ebay, installed it, and now she starts and runs fine in Neutral, But
as soon as I put it in gear now, she shuts off, I tested my side stand switch, and it operates correctly. Could it be still in the Change Relay? I just had to laugh and walk away. I'm going to reinstall the old relay and see if it still does it. Worked fine before, I just had to kick start it.
Thank you in advance,
Keith
 

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The change relay is just a transistor. When the motor is in neutral the change switch is off and the change switch relay is on. This grounds the starter circuit so the starter will work. When you put the motor in gear the change switch is turned on and the change relay is turned off and the starter circuit is not longer grounded.
When the motor is in neutral the change relay is on. the motor will fire thru the SCR 1 gate in the CDI at 7.5 degrees .The SCR 2 gate in the CDI is grounded thru the change switch relay.

When the motor is put in gear the change switch relay is turned off and the SCR 2 gate is no longer grounded and the motor will fire at 15 degrees BTC. This is to increase the RPM to compensate for the load from the torque converter. I would put the old one back on and see if the motor runs as it should and if it does then yes the used relay you bought is bad.
Put the old one back on and kick start the motor .Go from neutral to 1st and back to neutral and see if the RPMs change.

Bill H
 

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Discussion Starter · #6 ·
The change relay is just a transistor. When the motor is in neutral the change switch is off and the change switch relay is on. This grounds the starter circuit so the starter will work. When you put the motor in gear the change switch is turned on and the change relay is turned off and the starter circuit is not longer grounded.
When the motor is in neutral the change relay is on. the motor will fire thru the SCR 1 gate in the CDI at 7.5 degrees .The SCR 2 gate in the CDI is grounded thru the change switch relay.

When the motor is put in gear the change switch relay is turned off and the SCR 2 gate is no longer grounded and the motor will fire at 15 degrees BTC. This is to increase the RPM to compensate for the load from the torque converter. I would put the old one back on and see if the motor runs as it should and if it does then yes the used relay you bought is bad.
Put the old one back on and kick start the motor .Go from neutral to 1st and back to neutral and see if the RPMs change.

Bill H
Bill,
Thank you again for sharing your knowledge with me. it's funny, after church today I connected the old relay and it would not elect start in neut, but after kick starting, it also stalled when put in gear. I reconnect the replacement relay, it elect starts but stalls in gear. I disconnected the two pigtail leads that com off the relay, neit. lt. and gear indicators still work. It will start in neut only, and does not stall when put in gear. with the engine idling in gear I connected the light blu wire, still runs, then I touched the grn wire with a tracer, and she shut off. I restarted the bike and reversed the sequence , I connected the grn wire w/ tracer, still runs, then the lt blu wire, stayed running. No the issue is gone. Everything works as it should. I hate unexplained fixes.
Thanx again for you help. I'll be back if the Ghost comes back. LOL
 
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