Author Topic: Honda CB500RS no spark  (Read 797 times)

tevie54

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Honda CB500RS no spark
« on: January 29, 2023, 08:59:43 PM »
Having recently stripped and repaired a gearbox problem on the RS I replaced the flywheel with a heavier one from a Honda XL500R to make the engine less 'buzzy', this is a job I have done many times without a problem but this time it just wouldn't start. There was no spark.
Initially I thought it must be the new flywheel, losing it's magnetism or something so I replaced it with the original one but it made no difference. I didn't do anything different from what I normally do so I'm baffled by what it could be.
Any ideas?

themoudie

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Re: Honda CB500RS no spark
« Reply #1 on: January 29, 2023, 09:31:56 PM »
Aye tevi54,

Honda factory wiring diagram and a good multi-meter required. Then slowly, slowly, hunt the gremlin!  :(

Have you trapped the wire, coming through the casing?

Is there a multi-pin plug involved and are all the pins/connections in good condition?

Are the connections to the ignition switch all in place, or has a cable become trapped/shorting against the frame?

And on and on and on .........!

Go back through everything you disturbed/removed and if nothing found, go further. All the best.

Good health, Bill

tevie54

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Re: Honda CB500RS no spark
« Reply #2 on: January 30, 2023, 07:24:50 AM »
Hello Bill
I've gone over everything you say couple of times and even replaced the pick up on the advance mechanism side, it's almost as if the generator has stopped working while it was off.
I'm sending it back to Electrex for testing but in the meantime I guess I'll just have to keep checking everything I touched.

mthee

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Re: Honda CB500RS no spark
« Reply #3 on: January 30, 2023, 10:51:32 AM »
Had this happen to me on rerurning to the XBR rewire when I had left it so long, I had forgotten  about my hidden kill switch. I'm  sure yours will turn out to be less of a schoolboy's error.
Fear of the unknown does not mean the unknown needs to be feared

tevie54

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Re: Honda CB500RS no spark
« Reply #4 on: January 30, 2023, 11:58:40 AM »
Funnily enough the kill switch is next on my list of usual suspects

tevie54

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Re: Honda CB500RS no spark
« Reply #5 on: March 27, 2023, 09:33:52 PM »
A good clean up of the earths and a carb clean and away she went