Author Topic: BSA B25 with Wassel Vape Ignition  (Read 2150 times)

Offline ramwing7

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BSA B25 with Wassel Vape Ignition
« on: May 07, 2021, 09:20:16 PM »
I was recently riding my 1969 BSA B25 single cylinder motorcycle in which I have installed a Wassell electronic ignition.  It has worked well for a couple of years, but few miles.  But with no warning the bike suddenly stopped.  Examination showed there was no spark. There seem to b no loose or broke wires.
 I've used the trouble shooting directions in the Wassell Installation Guide and still haven't discovered the problem.  The following direction Guide is a bit unclear to me: 
     2) Using a multi meter check continuity through the stator plate. Set the meter to ohms. The
     resistance reading for each coil should be 73 ohms. Connect the meter to the black/white &
     black/yellow leads and the combined resistance should be 146 ohms.

I disconnected the plug with the black/yellow and black/white wires, inserted one multimeter probe into one side of the plug going to the stator unit and the other probe to ground.  The black/yellow wire showed NO resistance and the black/white wire showed 122 ohms.  I also checked continuity betwee the black/yellow and the black/white wires and got 212 ohms.
Question is:  Did I do that right?    If so, what does it mean?
Thanks
Ron
ps.  Any other suggestions to solve this will be much appreciated

Offline R

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Re: BSA B25 with Wassel Vape Ignition
« Reply #1 on: May 07, 2021, 11:55:51 PM »
I think at this point I'd be contacting Wassell.

If you can.
The fact its out of warranty (?) might loosen their tongues a bit.
If they have anyone who knows anything technical ...

The fact that those instructions are in the troubleshooting guide suggests it may be a common problem.
Not like it hasn't happened before then ... !!

I've had a leccy ignition fail, in the middle of about nowhere.
I carried the ole points in the toolbox, premonition ?
(not Wassell).

Offline iansoady

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Re: BSA B25 with Wassel Vape Ignition
« Reply #2 on: May 08, 2021, 10:39:58 AM »
I don't know the particular model (and Wassell as we know do knock out some dodgy stuff) but I would not expect anything but infinite resistance between either the black / yellow or black / white to earth. I assume there are 2 coils with 2 magnets on a rotor like the Boyer setup? Their trouble shooting is similar.

It sounds to me as though there's a short between the black / yellow and earth. And probably no connection between the 2 coils - they're generally connected in series.
Ian
1952 Norton ES2
1986 Honda XBR500
1958-ish Tre-Greeves

Offline ramwing7

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Re: BSA B25 with Wassel Vape Ignition
« Reply #3 on: May 08, 2021, 03:21:58 PM »
Fortunately, I kept the old points.  A shame to go back because the starting improved greatly.

And I'm trying to contact Wassell, but I get the feeling there's no one out there.   :(

Offline iansoady

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Re: BSA B25 with Wassel Vape Ignition
« Reply #4 on: May 08, 2021, 04:24:48 PM »
I'd check the printed circuit on the back (I assume there is one) for breaks and shorts to earth. That's the trouble with this type of ignition - they can just pack up with no warning whereas pointsusually start misbehaving for a while.
Ian
1952 Norton ES2
1986 Honda XBR500
1958-ish Tre-Greeves

Offline ramwing7

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Re: BSA B25 with Wassel Vape Ignition
« Reply #5 on: May 08, 2021, 06:22:08 PM »
It's a sealed unit, so there's no circuit to see.
The resistance across both coils is 123 ohms.  The installation troubleshooting books says it should be 173 ohms.

Is that enough to make it stop sparking?

Offline Rex

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Re: BSA B25 with Wassel Vape Ignition
« Reply #6 on: May 08, 2021, 06:23:34 PM »
Reading the diagnostic instructions again it seems they are to check the resistance singly and in together in series. It doesn't mention testing to earth/ground as far as I can see, and why "coils"?  Does this refer to components inside the EI unit and on the end of the crankshaft?
That said, it's Wassell stuff and although the coils are probably fine it's probably gone up the swanee somewhere else in it's circuitry. The acid test is, with juice to the unit and all connections made, there's no spark, and that usually means replacement in the world of EI.

Offline ramwing7

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Re: BSA B25 with Wassel Vape Ignition
« Reply #7 on: May 11, 2021, 02:54:23 PM »
Welp.  I took it all out and put it back in and now it has spark.
Go figure.  Must have been a shaky connection.
Stuff like that makes me crazy!!

Thanks to everyone for your input.  It was most helpful.