electronic ignition... no spark

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johnny650
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Sun Nov 25, 2018 5:31 pm

losing the will to live now :roll:

Ok have fitted new electronic stator , AC regulator and PX CDI and there is a very weak spark from the stator green wire but zilch from the CDI when connected ...

I tested the Stator as per Stickys manual and get 475 ohms on the red and 93 ohms on the green wire, white earth wire to chassis is a short so stator earth ok.

How strong should the spark be from the stator ?

I'm guessing the the problem is likely to be the new CDI unit . Is there any way these can be tested ?
I have only connected the green stator wire and the yellow earth wire of the CDI to the body and frame.
As I don't need lighting I have not connected the 3xpin regulator and yellow lighting wires yet.

I have ordered another 12v CDI but could a 6v points coil be used to provide a spark ?

firekdp
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Sun Nov 25, 2018 6:00 pm

johnny650 wrote:
Sun Nov 25, 2018 5:31 pm
I have only connected the green stator wire and the yellow earth wire of the CDI to the body and frame.
You need to connect the CDI up fully to get a spark. The thyristor inside the CDI can't discharge the capacitor into the HT primary without a pulse from the red!

johnny650
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Sun Nov 25, 2018 6:15 pm

sorry I wasn't very clear about this was I ....

The CDI is correctly wired up with red from the pickup, white from the stator earth, green from the LT coil and the yellow earth tag connected to the main earthing point.

It is just the yellow wires and the regulator that isn't connected but they are a separate issue.

firekdp
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Sun Nov 25, 2018 6:27 pm

Ah, OK. If you have a small red LED, connect this between the red and white on the CDI (anode to red). This will tell you that the pick up is sending a pulse.

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garry inglis
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Sun Nov 25, 2018 6:35 pm

Are the other earth connected ie back light to body from the loom and maghousing earth to leg then body with the regulator and the earth in headset you still need the earth set up to help start the bike I can run my engine on my stand with just the earth off a coil but on the scoot I would rec
Fittling all earths my mate rebuilt his scoot and couldn't get it started and after searching found no rear earth on backlight to body

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johnny650
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Sun Nov 25, 2018 7:42 pm

firekdp wrote:
Sun Nov 25, 2018 6:27 pm
Ah, OK. If you have a small red LED, connect this between the red and white on the CDI (anode to red). This will tell you that the pick up is sending a pulse.
brilliant thanks firedp i'll try that tomorrow. ;)

johnny650
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Sun Nov 25, 2018 7:47 pm

garry inglis wrote:
Sun Nov 25, 2018 6:35 pm
Are the other earth connected ie back light to body from the loom and maghousing earth to leg then body with the regulator and the earth in headset you still need the earth set up to help start the bike I can run my engine on my stand with just the earth off a coil but on the scoot I would rec
Fittling all earths my mate rebuilt his scoot and couldn't get it started and after searching found no rear earth on backlight to body

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yes garry I have a new earth strap and always make sure of good earths but I'll double check tomorrow . Wouldn't be the first time I've done something stupidly obvious doh... :lol:
I've actually disconnected the green wire from the loom as well to make sure its not earthing in the loom, ignition switch or headset somewhere.

I have got a very weak spark from the stator green wire I'm just not sure how weak it should be normally..

mick1
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Sun Nov 25, 2018 7:57 pm

How do you know it's a weak spark ?

A visual won't give much of an indication, does the engine fire up ?

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garry inglis
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Sun Nov 25, 2018 8:16 pm

If you have all connected try for spark with the plug out touching metal if no spark try different plug if no spark take cap off and try the cable against metal if the spark is there it's your cap and just work back double check everything and Inbetween take tea breaks fag brakes before you smash it up with a big hammer

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johnny650
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Sun Nov 25, 2018 9:48 pm

mick1 wrote:
Sun Nov 25, 2018 7:57 pm
How do you know it's a weak spark ?

, does the engine fire up ?
No... it doesn't have any spark ;)

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