Negative-Ground Boyer Box

Folks

I need a used Boyer box for my E-Bay chopper that someone converted to negative ground. [Ad. in the Wanted section - L.A.B.]
It's got a Boyer setup--I've got two Norton-type Mark III's and a 12-volt Triumph/BSA Mark III unit that's supposed to work with either negative- or positive-ground systems. None seem to work. Do Triumph and BSA twins have CCW camshafts?


The 12-volt Triumph/BSA box (Box00023) has instructions stating that the box can be used with negative- or positive-ground systems as long as the coils are fed from the energized side.

I wonder how the box can work with CW and CCW camshafts, if BSA and Triumph twins have opposite camshaft rotation?






Tim Kraakevik
kraakevik@voyager.net
630 474-9164

kraakevik said:

Do Triumph and BSA twins have CCW camshafts?

Click to expand...

BSA = Yes
Triumph = No

kraakevik said:

I wonder how the box can work with CW and CCW camshafts, if BSA and Triumph twins have opposite camshaft rotation?

Click to expand...

It doesn't make any difference to the electrical installation, the rotor magnets are set at the other side of the pickup coils for opposite rotation. The Boyer pickup backplate has two timing holes, one for clockwise rotation and the other for anti/counter clockwise rotation.