A3 weak spark

I bought a 84 silver bullet it has a new plug coil and condensor and points. but the spark is almost nothing. When I put a screwdriver in the plug wire and ground it to the head I see a tiny little spark. With the plug in and grounded to wheat I can only see a spark in the dark. Is my ignition coil on bad ? Any ideas ? I’m new to this.

Re: A3 weak spark

Did they put the correct coil on it? Have you set the new points at .014"? Fourteen thousandths of an inch.

Re: A3 weak spark

Ducati ignition? Do you have a yellow, blue and a black wire coming out of the stator?

Re: A3 weak spark

Well I’m not sure I bought it from a guy that put it on. It’s orange and black. I’m a little suspicious of it though because I can’t find the orange and black ones for an a3.

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Re: A3 weak spark

Yes

Re: A3 weak spark

> Josh Kiser Wrote:

> -------------------------------------------------------

> Well I’m not sure I bought it from a guy that put it on. It’s orange and

> black. I’m a little suspicious of it though because I can’t find the

> orange and black ones for an a3.

That's a Chinese bike coil. It will work though. Why is that blue wire in hooked on the stator plate? Post a better pic of the stator plate. I'm thinking the blue wire is your problem.

Re: A3 weak spark

By the looks of it , that coil is the least of your problems .

Definitely double check all the wiring for correct path .

And , be sure that all connections are scratch tight and clean .

Re: A3 weak spark

I don't even see a primary ignition coil on your bike. How could you be getting spark at all?

Re: A3 weak spark

Pics

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Re: A3 weak spark

Points just don't look right to me. Are you sure they're the right ones for that ignition?

Also,replace that screw on the points hold-down.

Re: A3 weak spark

^i think dons onto something

https://www.treatland.tv/tomos-A3-A35-OEM-points-stator-p/oem-tomos-stator-223171.htm

u want the points for cw direction i think, just look at your felt pad cw. and the treats stock stator.

Re: A3 weak spark

No I’m not sure... they seem to be working and I was able to get the gap set. They don’t look right to me ether but they open and close when they should.

Re: A3 weak spark

Try grounding the blue wire to the motor and see if it fires

Re: A3 weak spark

Looks right to me

Screenshot_20190107-202514.png

Re: A3 weak spark

Well the one in that link won’t work for me mine is an 1984. That’s only for the older a3. If I could find just the right one I would buy it. I am thinking about buying the Cdi upgrade from treatland for $150. But I’m worried. I’m good at replacing part. Not to technical though. Any link to the right part?

Re: A3 weak spark

I had it off in that pic testing with multimeter.

Re: A3 weak spark

It looks to me that you have the right stator .

Make sure that the points are pristine clean . Even a fingerprint can foul them .

Then try Stephen's suggestion of grounding the blue wire . Back to the stator plate .

Leave the blue grounded to the coil . Just run a jumper wire from there down to the plate . If that works make it look pretty later .

Re: A3 weak spark

^i guess im wrong again, anyways make sure nothing on the hot side of the ignition coil is not touching ground, it'll kill spark. suspect are the wires off the condenser possibly touching the condenser body. possibly try another known good coil, did u try grounding blue wire?

Re: A3 weak spark

> pat splat Wrote:

> -------------------------------------------------------

> ^i guess im wrong again, anyways make sure nothing on the hot side of

> the ignition coil is not touching ground, it'll kill spark. suspect are

> the wires off the condenser possibly touching the condenser body.

> possibly try another known good coil, did u try grounding blue wire?

Yes,just one little stray strand and it's trouble...……...been there,suffered that!

Re: A3 weak spark

I ran a wire from one of the mounting screws for the stator to the blue wire. No change. Still just the faintest little spark that I can only see in the dark.

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Re: A3 weak spark

Pic

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Re: A3 weak spark

Try this same set up , but , disconnect the wire that goes to the kill switch .

Re: A3 weak spark

Must be an optical `contusion', but it doesn't look like the coils are aligned with the magnets in the flywheel? Just must be the photo?

Re: A3 weak spark

Bad condenser?

Re: A3 weak spark

So I have also tried it with the kill switch disconnected with the same results. I’ve tried everything. Plug coil condensor points. So I was thinking of upgrading to the cdi version. Will this two wire version work for me? That would have to solve my spark problem...right?Thanks.

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Re: A3 weak spark

I’ve measured it and it is 90mm.Edited 1 time(s). Last edit at 01/10/19 07:09PM by mclovnt.

Re: A3 weak spark

ok a little more investigation, u got a mutimeter right, set it on continuity.

1. note : using like color wires makes life easier. get rid of black wire sticking outta left side under stator. u should only use the wires coming outta the rubber gromet. black to the hot side of coil and blue for external ignition ground.

start by disonnecting hot black to coil and blue from ground.

check coil terminal contunuity to end spark plug cap. good? if no continuity then something up.

2. w points open. Check from points screw to outside black wire, good? if not then theres a break in wire somewhere. check from points terminal to ground, nothing on the hot side should be grounded. if it is...then search wheres its touching or grounding out your spark.

reclean and set points, clean all grounds, shiny metal clean.

ground blue wire, black wire to coil. spin, u should get spark. oh wait, is it a non resistor cap?

Re: A3 weak spark

Well I’ll give it a try. I don’t know what a non resistor cap is.

Re: A3 weak spark

ngk 8381, $3 at auto store. untwist and twist on. u can measure yours to see.

Re: A3 weak spark

> Josh Kiser Wrote:

> -------------------------------------------------------

> Well I’ll give it a try. I don’t know what a non resistor cap is.

A resistor cap will measure about 5,000 OHMs between input and output .

A non resistor cap will measure very close to zero OHMs .

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