Back to technical page

Boyer Bransden alternative analogue or digital ignition sets
(Through the links "Britbike", "Britcycle" and "Kirby Rowbotham" on this page, you can find information on the digital Boyer set).

Lars Bendsen from Denmark succesfully installed a Boyer Bransden analogue ignition system on his Moto Morini 3½ and Lars has sent me the following information. Boyer Bransden has not got an internet site :-(

Please note:
1) Boyer Bransden has not (yet) an own website :-(
2) On this page three very interesting links to sites which offer more information :-)

Boyer Bransden produces a system for 90o V-twins. This ignition can be converted into an alternative ignition for a Moto Morini V-twin (with it's 72o angle between the cylinders). The triggerdisc of this 90o set needs to be converted to suit the 72o angle on the Morini. A local workshop made the conversion by producing a new triggerdisc with a lathe and a CNC millingmachine. It should also be possible with a conventional millingmachine with dividinghead with an angual error of 0,01 deg. Apart from this conversion, only a few extra spacers are needed.

According to Boyer Bransden, there is no difference in advance curves in any of their analogue systems, so the processor of the system used by Lars is stamped "Triumph-BSA twin". But a Boyer Bransden, stamped "Norton" would also work, according to Lars.

  • The system consumes between 1.5 and 1.9 Amp. This is between 18 and 23 Watt, or 20% to 25% of the total electricity production of the Morini 100 Watt alternator. (Moto Morini models with an electric starter have a more powerfull 150 Watt alternator).

  • The max. advance of both analogue and digital Boyer Bransden ignition is (only) 20o. The original Ducati Elettrotecnica reaches 34o on the 350 and 30o on the 500cc model.
For more details on the Boyer Bransden systems (also digital), see:
Britbike
Britcycle
Kirby Rowbotham
this is the Boyer Bransden
analogue processor

Address, telephone:
Boyer Bransden
Findsbury House,
Cox Lane, Detling
Maidstone Kent ME14 3HE
United Kingdom

Phone +44 (0)1622 730939
Tech Hot-line +44 (0)1622 737040 4-5 PM
Fax +44 (0)1622 730930

To use an analogue Boyer Bransden system nn a Moto Morini V-twin the following parts are needed:
  • KIT00048, MK3 V-Twin conversion
  • (  61.58 or 87,05)
  • COIL00004, 12 volt Dual output coil 4,5 Ohm primary
  • (  30.67 or 43,35)
  • COIL00006, Heatsink for coil 00004
  • (    4.97 or 7,03)
    postage & packing (    9.00 or 12,72)
    VAT (  18.60 or 26,29)
    Total price incl. p&p and VAT ( 124.82 or 176,44)


    The components lined up,
    from left: Spacer made from POM,
    (plastic, polyacetal or "Delrin")
    to lift the pickup plate free from
    the housing.
    Top, original triggerdisc
    (copper colour),
    below new disc with 143,35 deg
    between the triggermagnets plus
    aluminiumspacer and original
    Morini nut. Pickup-plate with two
    rubberspacers to keep soldering
    on the backside free.
    triggerdisc fitted
    behind the timingcover.
    processor connected and
    located under the fueltank
    a close-up of the previous
    view

    Note: the electronic rev. counter of the Morini V-twin needs recalibration with a 500 Ohm trimpot in series with the original. Originally there is one 500 Ohms trimpot so the best way to do it is replacing this component for a 1 kOhm trimpot. (Easier said than done, as the Veglia instrument needs to be opened for this and new, chrome rings to close it again are hard to get).

    Back to the technical page
    Back to index page