Author Topic: Motor earthing issue  (Read 685 times)

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Online hardy

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Motor earthing issue
« on: June 09, 2017, 03:28:52 AM »
Hey guys,

I started my bike this arvo in the garage with door down, (dumb idea, but found the air leaks in the garage lol) but while it was semi dark I noticed that the spring that covers the throttle cable was touching and earthing out on the barrel...strange

Is there a designated earth for the motor? Or have people installed a second earth to compensate?

Any ideas welcomed, bike starts and runs well.


Online BS Mechanic

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Re: Motor earthing issue
« Reply #1 on: June 09, 2017, 01:39:59 PM »
You should have a black-white wire coming out of the alternator and going to the battery negative. This grounds the engine.  There's also a black wire going from the battery negative to frame ground, although I can't quite remember where on the frame it goes.  Schematic in the shop manual shows the wires and connections.

Offline BRT-GTR

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Re: Motor earthing issue
« Reply #2 on: June 10, 2017, 07:20:07 AM »
             The longer of the black earth wires coming from the battery negative goes to the rear frame mounting bolt on the voltage regulator. (The shorter wire goes to the rear terminal on the rectifier). It's not arranged quite as shown in the electrics schematic.

           With the motor being rubber mounted, it's not a bad idea to install a better, separate earthing wire for the engine. The long 6mm nut on the alternator strap provides a good connection at the crankcase and is easily connected to one of the adjacent frame bolts for the rear engine mount. Not original but helps prevent stray currents from trying to find an alternative route to earth on the frame. Surprised BS didn't fit one.
« Last Edit: June 12, 2017, 09:16:04 AM by BRT-GTR »
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Online hardy

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Re: Motor earthing issue
« Reply #3 on: June 10, 2017, 06:15:49 PM »
Thanks for your replys guys. I will chase the wiring and check, but most likely install a better earth as suggested.




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