tech22

In the past I have written several articles about how Boyers work. I
admit they were conjecture as the schematics were not available to
me. Assumptions were made by me based on my experience and
advertising claims. Some of these errors have been corected in the
past and some still need correction. My insight has been heightened by Dave Comeau's de-potting of both an Analog and Digital Boyer which revealed the system schematics. Boyer has never been willing to divulge to me any of their unit's inner workings.

So here it goes:

Both Analog and Digital Boyer DO NOT use Capcitive Discharge
Ignition (CDI) circuitry. Both use a transistor switch that emulates
the actions of the common points with none of the advantages of
a true CDI ignition. The CDI advantages NOT there are: fast spark
generation which increases the possibility of gas fouled plugs
firing; capability of using large spark gaps to increase the spark
area exposed to the fuel mixture to increase the reliability of the
ignition process.

The Analog unit uses analog circuit techniques to control the
advance curve while the Digital unit uses a specific Integrated
Circuit configured like a computer and run by a stored program.
The digital unit allows the choice of several different advance
curves via switches on the black box (actually red, I believe).

Both the analog and digital units use magenetic triggering via a
rotating magnet assembly and fixed coils inside the former points
cavity.

While certainly the analog unit and probably the digital unit made
by Boyer are good units, priced fairly, they lag behind modern
technology where virtually every modern vehicle and every modern
after market ignition system offered for cars are CDI. But the
Boyers are cheap, decrease maintenance of the bike, are
reasonably reliable, and have a good following of users. They are
just not state of the art as I first assumed. The Analog Boyer still
represents the best bet for Brit bike owners.

One caution voiced by one dealer who sells the digital unit is that
it absolutely requires that the system utilize one of the following:
resistor plugs or resistor plug wires or resistor plug caps. It seems
that the embeded computer is very susceptable to ElectroMagnetic
Interference (EMI) generated by the mere firing of the plugs. The
bike just stops running and nothing short of a power off/ power
on cycle, which resets the computer program, will bring it back to
life. The computer looses it place in the program from the EMI and
quits. Note also that the digital unit requires that there be a
battery and that its' condition be good: no batteryless operation is
possible and you had better have a good battery in there as well.

I hope this corrects my mis-deeds of the past and enlightens all to
the Boyers operations. Use a Boyer of your choice, just be aware of
what you are getting.

LDBennett