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@slick_89 avatar
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Hooked
1971 Sprint with P200e
Joined: UTC
Posts: 153
Location: Essex, England, Great Britain
 
Hooked
@slick_89 avatar
1971 Sprint with P200e
Joined: UTC
Posts: 153
Location: Essex, England, Great Britain
UTC quote
The 4" wire (yellow) with a ring terminal on it, is it for grounding?
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Ossessionato
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Ossessionato
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UTC quote
I always wondered that too?? It's bolted on by one of the flywheel cover bolts I think. I looked at my motor the other day and it's disconnected.
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Banned
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Location: Washington MFing DC
 
Banned
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Location: Washington MFing DC
UTC quote
Re: whats this Coil wire for?
Slick 89 wrote:
The 4" wire (yellow) with a ring terminal on it, is it for grounding?
Yes.
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Ossessionato
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I'd better hook that shit back up
@rover_eric avatar
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Moderator
1965 Vespa SS180, 1963 Lambretta LI150
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Location: Detroit, Michigan
 
Moderator
@rover_eric avatar
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
UTC quote
It's a redundant ground for your CDI.

See, you had HT coils originally made of Bakelite ..which is non-conductive ...so the old bakelite coils had both a GROUND and a HOT (red ) lead coming off of them.

Then you had the PX125 style black HT coils ... which had that big metal mount that bolted to your engine case, and only 1 ( hot - red ) lead coming off the top. The black was unnecessary because the HT coil itself grounded to the engine case.

Now, the Ducati CDI you've got is encased in black or blue plastic. The White wire ( i believe ) is a ground wire from the stator ... but in order to ground the whole CDI assembly, you use that little yellow wire with the ring tab.

They still work if you don't...but i think it's a beneficial thing to use ( until the yellow wire inevitably falls off ).
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Ossessionato
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Ossessionato
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The yellow wire with the ring connector uses one of the flywheel cover bolts for mounting correct? You are right...it just falls off somehow.
@rover_eric avatar
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Moderator
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
 
Moderator
@rover_eric avatar
1965 Vespa SS180, 1963 Lambretta LI150
Joined: UTC
Posts: 6980
Location: Detroit, Michigan
UTC quote
Yeah..it's just a redundant ground to the engine case - uses a flywheel shroud bolt to attach.

And it always snaps off where it meets the plastic of the CDI because there's no strain relief and eventually the vibrations crack it off.
OP
@slick_89 avatar
UTC

Hooked
1971 Sprint with P200e
Joined: UTC
Posts: 153
Location: Essex, England, Great Britain
 
Hooked
@slick_89 avatar
1971 Sprint with P200e
Joined: UTC
Posts: 153
Location: Essex, England, Great Britain
UTC quote
thanks all.

BTW this is why I'm fitting a new coil

External inline image provided by member with no explanatory text

I was getting a weak and inconsistant spark
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Ossessionato
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Ossessionato
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UTC quote
Looks like a blue box that caught on fire

Yeah get a new one
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