Ignition System Triumph BSA Unit Construction Twins 12 volt

Ignition System Triumph BSA Unit Construction Twins 12 volt

Boyer Bransden MKIV
High Power Ignition System
Triumph & BSA Twins
Unit Construction 12 Volt
Select Currency
NZ$ 287.50
NZ$ 249.00 including GST
Purchase Qty:

Boyer Bransden Electronic Ignition Kits - Over 50 years Proven Performance

In 1969 Ernie Bransden designed and patented a miniature electronic ignition that was a fraction of the
size and far more efficient than any of its competitors. Since that time various electronic ignitions and
manufacturers have come and gone, but Boyer Bransden have been in constant production.

Today, Boyer Bransden produce one of the most efficient ignition systems in the world. All systems
are carefully hand built in the UK under the ethos of supplying hardy products that last.

The improved MKIV versions are designed to improve the timing stability if engine starting with a very low or variable battery voltage. The design changes are internal and do not affect the external appearance of the unit. Identified by the 'MKIV' caption on the label the new units are fully interchangeable with previously produced MK3 and MK1a units, and offer improved performance for both electric and kick start machines

British Spares Ltd offer full testing facilities, spares back up, and warranty claims processing for
Boyer Bransden ignition systems and components.

Boyer Bransden Electronic Ignition systems fire all coils together in series and therefore share the available voltage across the number of coils on your motorcycle.

For this reason, it is recommended that you install:

12 Volt coils on single cylinder machines

6 Volt coils on twin cylinder machines

4 volt coils on triples (due to unavailability of reliable 4 volt coils, most triple owners will have to use 6 Volt coils, which do operate very satisfactorily.)

A satisfactory 12 volt charging system with efficient voltage regulation will be required on models that were produced originally with 6 volt electrical systems.

These kits are used to replace the original Lucas Points Plate Assembly (and Condensers) and the Advance and Retard Mechanism. The Boyer Bransden Electronic Ignition is proved to be very reliable, easy to fit, with no maintenance.
For the best results setting ignition timing a stroboscope should be used.

12v Boyer Bransden Micro MKIV Ignition Kit for BSA & Triumph Twins and Royal Enfield Interceptor

Suitable for positive or negative earth (6V coils are recommended)

Fits the following 12 volt Unit Construction models with timing side points housing:

  • Triumph Bonneville/Tiger/T100/T110/T120 /T140/140V/140E
  • Trophy, TR6, TR7, TR5T Trophy Trail Adventurer, TR7T, TR65, TSS, TSX
  • BSA A50 A65 T65


  • Royal Enfield Interceptor

(Models originally produced with 6 volt electrics can be converted to 12 volt fairly simply, please contact us for further information on this)


Product Search

Price From
Other Filters

Connect With Us

View Cart


On Sale

Best Sellers

New Items