21 replies to this topic

[cafe55]

Hi Folks,

I've recently been trying to chase a 'no spark' condition on my 95 Section. I started with a new plug then checked continuity on the plug wire and finally tested the coil for its respective ohms according to earlier posts here. Though I was getting some inconsistent readings with my meter, I'm thinking the coil is ok. This was even after replacing with another Section coil and still getting no spark against the head.

My suspicion now is that it could be the stator. Does anyone know what wires I should test on the stator and if so, what resistance values I should look for? - I believe the wires are white, green, red and yellow.

I haven’t yet gotten behind the fly wheel to check for chaffed wires or burned leads but also was uncertain if the nut on the crank was a reverse thread? - don't want to strip that with my air impact.

Also, could I be going the wrong direction here in that it could be a faulty voltage reg., rectifier or cdi unit? How does one test these?

It's frustrating that Fantic didn’t have a specific shop manual for this bike!

Any help and pointers would be greatly appreciated.

Isaac,


San Luis Obispo, CA. USA

[grib]

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[grib]

The flywheel nut is a normal right hand thread. The white green and red wires are the ignition stator; red is power, green is trigger, white is ground, the other wire (usually brown) is power for the lights, if its not disconnected disconnect it, at least until you have solved your spark problem. There is no separate CDI; every thing is built in to the coil. I'm not sure what you should be looking for in term of resistances, the only wiring diagram I have has written on it (by hand) red/white 110 +/-5, green/white 500 +/-20 but it doesn't say whether these values refer to the coil or the stator.

[cafe55]

Grib,

Thank you for the reply. I'll go ahead and remove the fly wheel and see if anything looks abnormal. If everything looks good on the outside, I'll check the resistance as you noted. If it turns out to be the stator, curious if you've ever had one rewound? I suppose trying to locate a replacement stator for these bikes is like trying to find hens teeth. I do have a lead from my local Ducati mechanic on an outfit in Los Angeles that rewinds coils. Hopefully, I won't need them and it will be something obvious like a loose or worn wire. I'll keep digging............

Thanks, again.

Isaac,

[grib]

I've never had one rewound but it shouldn't be too hard to find a used one, I think you could probably use a stator from any 212/250 from a 241/301 onwards. I have used a 96 Section flywheel on a 245 and despite some small visual differences it is functionally identical.

[cafe55]

Grib,

I was able to remove the flywheel with an auto steering wheel puller. Worked fine but it took some of force -looks as if it had never been off since the factory.

All the wiring looked fine - no burned or chaffed leads to speak of and all looked very clean. The stator plate appeared as it had not shifted and was dead on the index mark.

I then checked resistance on the leads with the green/white @ 484 and red/white @ 102. The red/white seemed to be out of spec just by a hair of the 110+/- 5 but I'm thinking this might be slight variability in the meter. At this point it seems the stator is OK unless the discrepancy in the red/white spec is enough to cause a problem?

I'm thinking of back tracking and focusing on the rectifier. I have a few full-wave four post bridge rectifiers and not sure if they would have the same application spec and exactly how to wire them - guess I could just trial and error it and see what happens.

There is also, what appears to be the regulator, though I'm not positive. It's about 1.5 x 3 inches with cooling fins and sits across from the rectifier on the frame. I'm not sure how this works in conjunction with the rectifier?

Any other comments/ideas?


Thanks,

[shyted]

Hello cafe 55, just another note,try another meter and if the readings are the same (very close ) then your on the right track.
BUT ...strangly enough i was reading a report on a web site called classictrials about Fantic stators and regulators and their malfunctioin ,so they might be worth contacting as well if you run out of ideas and need to get more info if you can't find it here .
As to your comment about information for diagrams ,you can get some info from a free pdf off Bob Wrights website,but im thinking of making my own complete work shop manual in the future (with pictures) but thats going to take time .
Best of luck with your diagnostics and let us know the outcome and what happend next.
Hope that helps and you get fixed up .
Shy

[grib]

The only things you need for the bike to run are the red green and white wires, the rest is all lighting etc, don't try and wire in a regulator. If you have a good stator and a good coil then it has to be either the wiring between the two or the plug/plug lead/plug cap. I would check the wiring between the stator and coil and use a brand new plug, plug cap and lead.

Wiring diagram:

Edited by Grib, 09 May 2012 - 12:45 PM.

[cafe55]

Shy-

Thanks for the post. Been gone a couple days so havent been able to work on the bike and reply.
I'll be getting my hands back on it tonight.

Just for grins I'm going to take the stator completley out and have a look behind just to see if all is well. I'll also try another meter and see what kind of readings I get. I'll also check out classictrials and Bob Wrights site and see if I can gleen anything.

As soon as I find the problem with this bike I'll be sure and post to let everyone know.


Grib-

I'll go ahead and stay away from the rest of the other elec. components. I'm glad you mentioned this so I can rule these out. As a side note I was able to find a wiring diagram off of the web. The source said it was from a 96 Fantic but noticed some of the wire color coding is different and as well as having lights and turn signals on the diagram?

As I mentioned to Shy I'm gonna take a closer look at the stator though the resistance seemed good. I've allready tried a new plug but dident try a new HT wire. I'll give that a shot. At this point it must be something simple that I have been over looking!

Isaac,

[grib]

I would use a new plug cap as well - they don't last forever, infact a friend of mine laughed out loud when he was chasing an ignition fault and I suggested it could be the plug cap as it was 10 years old; instead he changed every other ignition component before conceding that it could be the cap - which it was.

You could check for a spark from the end of the HT lead with no cap fitted just to eliminate possible duff components.

[cafe55]

Grib,

OK. Finally got time to reassemble everything with a new spark plug, spark plug cap and wire. All this was assuming the resistances in the electric components were checking out including continuity on the stator lead wires and that by some miracle of God I would get spark back. Well it looks like there were no miracles tonight. Kicked and kicked until I was sweating bullets - still no spark.

Here are my conclusions after some more head scratching and additional internet research:

1). The CDI/Coil? Still suspect (including the second unit I purchased - though, the values were the same - assuming I was checking correctly) since I have not encountered consistent values to test resistance at the connecting spades between white, red, and green terminals (BTW, there is a brown/white wire that I have not identified in all the research coming out of the CDI/coil with a ring terminal that connects to the regulator -anybody know what it's for - ground/earth?)

2.) The pickup coil (pickup)? - small blk box 3/4x1/2 inch sitting @ about 6 o'clock on the stator plate w/ the red wire lead. The resistance was 107.2. The closest spec I could find - Ducati but non-fantic was 30-40 ohms. Is this good, bad or does it even matter?

3.) Bad green wire between the low-tension/charging coil, sits @ about 5 o'clock, guessing not one of the lighting coils because its wrapped with white fabric tape? Though I had continuity on its lead wire, is it possible the correct flow of current is still being impeded through the wire?

All this is becoming nerving........

BTW- Thanks for the wire diagram. It was allot better than the one I found on line since it had some ohm values.

Isaac,

[grib]

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[grib]

Isaac, the ring terminal on the coil must be grounded to the frame; without that you will never get a spark.

[grib]

I have just measured a good stator: 117.4 ohms Red/White and 469 ohms Green/White. These are pretty close to your values from post #5 and those written on the wiring diagram - it sounds like your stator is good to me. (BTW I think I have got red & green the wrong way round in post #2).
The coil with the white tape is power for the ignition and the black box is the trigger, the other 4 coils power lighting and horn.

[cafe55]

Grib,

I've been performing two separate resistance tests - resistance on the CDI/coil between spade connectors and a separate test between the leads of the stator.

So what you are saying is the resistance values at the CDI/coil spade terminals where the leads from the stator would normally attach - green spade to white spade and red spade to white spade between them should have the same resistance values as between the leads attached to the stator - green lead to white lead and red lead to white lead?

I found this article on testing Ducati ignition on the web however; the values and wire colures don't really seem fit the fantic/ducati system. I tested the values for the CDI/coil (what they call the black box) against theirs but didn’t have any conclusive readings. This may be a system for aircraft.

http://www.800-airwolf.com/pdffiles/ARTICLES/part%2058.pdf

The brown/white striped wire with the ring terminal coming out of the CDI/coil was connected to what appeared to be a ground/earth junction at the regulator as I found it. Mostly, I was curious what its function was.

Not sure where to go from here. Should I pursue the possibility that the pickup coil has failed?

[grib]

cafe55, on 18 May 2012 - 11:15 PM, said:

So what you are saying is the resistance values at the CDI/coil spade terminals where the leads from the stator would normally attach - green spade to white spade and red spade to white spade between them should have the same resistance values as between the leads attached to the stator - green lead to white lead and red lead to white lead?

No, in my earlier post I said the green wire from the stator was the trigger and the red was power but that is only the case with earlier Fantic ignitions, on the later ignitions like yours the red stator wire leads to the trigger and the green is power.

It sounds like your stator is fine. what resistance readings do you get from your two ignition coils?

[cafe55]

Grib,

Finally got back to the bike. Tests for resistance between the male spade connectors on the Coil/CDI are as follows:

Coil # 1, White to Green = 87,600 ohms
White to Red = 365 ohms

Coil # 2, White to Green = 87,800 ohms
White to Red = 367 ohms

At this point I don't believe the coils are bad with values so close, as you also mentioned. Unless, of course their both bad!

I'm thinking of ordering a new pickup since it seems everything else has checked out. Problem is finding it.

Wanted to say thanks again for your input and advice. I'll keep digging........

Isaac,