GP200 electronic resistor

[firekdp]

Just read the article by Adam on these:-
I've also been looking into this system for some time viewtopic.php?f=7&t=1077&view=next

I believe these were fitted from the outset by innocent as it's a system adapted from Ducati motorcycles of the time and these did incorporate a resistor in the cut out circuit. The resistor is also mentioned in a Lambretta dealers letter to help fitters understand/diagnose the system (although no mention is made of it's position).
It could be fitted anywhere in the cut out circuit, but placed where it is, inside the loom, keeps it out of harm's way.

I initially, like others, thought it was designed to protect the feed coil from damage, However, later Ducati Vespa systems, using similar stator outputs, don't suffer from problems attributed to this and no resistor was fitted to them. So either the resistor was there to, IMO protect the earlier 323901 cdi, or the resistor was a precautionary measure and not really needed at all.
My attempt at making one

[firekdp]

https://www.flickr.com/photos/145830872 ... ed-public/
https://www.flickr.com/photos/145830872 ... ed-public/

[Lamaddict]

Yes, I built a thicker wire into a new loom for my original 6v electronic set up. Seems like it was more of a drain wire soaking up excess current.
I took of my original set up and changed it out for a SIL set up because the lights were so dim using the original system. Putting the rear brake on and the front light would dim to hardly anything.

[firekdp]

I'm afraid simply fitting a thicker wire into the loom would have no effect.
Out of interest, did you get the non sparking system you posted about working again.

[Adam_Winstone]

So is that the one that you're made in the photos? If so, where did you source the parts from (crimps and resistor wire of the correct Ohm rating)?

Adam

[Lamaddict]

I'm afraid simply fitting a thicker wire into the loom would have no effect.
Out of interest, did you get the non sparking system you posted about working again.

Yes thanks, got it sorted. It's was an earth fault in the ignition switch. The fault also coincided with the float sticking due to ethanol in the damn petrol. I swapped it out for a SIL float and it was okay.

I couldn't see the difference between my length of thick wire and Innocenti's thicker wire. I don't measure the resistance.

[firekdp]

So is that the one that you're made in the photos? If so, where did you source the parts from (crimps and resistor wire of the correct Ohm rating)?

Adam

Yes, the crimps I made myself as I couldn't find any like it.
I'd wait on the resistive material as I don't know whether it is actually suitable until I test it. I

[firekdp]

If the missing resistor is causing the CDI to fail it may be possible to get it working again with a small external mod, but again I can't confirm this without testing a broken one.

[Adam_Winstone]

I too looked and struggled to find those crimps (failed) and got nowhere with an appropriate resistance wire, although I did get taken down the route of ceramic composites. Please keep us informed of progress?

Nice work

Adam