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Cb750K7 Electronic ignition units

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Flyingscotsman3:
Hi All,
Recent owner of cb750k7 reg number VAH 182S.
Am planning in the near future to fit electronic ignition, & just wondered if anyone has any recomendations, as in best type, & maybe where to buy from?.
Thanks Kev

Trigger:
Dyna is about the best but not cheap.

AshimotoK0:
Back 'in the day' I designed and built a CDI system which retained the points and ran it on my first 400/4 for 20k miles (had one capacitor go short) but apart from that worked great and never adjusted or changed the points after first fit but literally 5 min job to return to standard ignition. Left it on the bike when I sold it. The expensive/hard to get bit at the time was the inverter transformer to convert the 12v to 400 VDC but you can now buy 100W plug in converters for cars for next to nothing, so one day I will update the design using one of those and put one on my CB750. The  one  I made was back in '79/80 so I reckon capacitor technology (the one which discharges 400v into the coil) have come on since then. Used the standard Honda coils BTW with no problems. I stripped down one of the modern car plug-in mains inverters last week and the quality looked surprisingly good (had USB power socket on it too !!)

Cheers ... Ash D

Johnwebley:
I fitted Boyer to my 500-4 about 1978, !!!!

 still use it,easy to set up,only replaced the box once,about 12yrs ago,


I am happy with the performance and reliability ,

think it cost me about £27 originally
 
may be dearer now

AshimotoK0:

--- Quote from: Johnwebley on May 31, 2014, 04:09:29 PM ---I fitted Boyer to my 500-4 about 1978, !!!!

 still use it,easy to set up,only replaced the box once,about 12yrs ago,


I am happy with the performance and reliability ,

think it cost me about £27 originally
 
may be dearer now
--- End quote ---

I have one of those on my  400/4 (it was on it when I bought it)  but it's different than a CDI as it just replaces the points with inductive pickups and switches the coil current with transistors. The capacitor charged to around 400v on a  CDI discharges across the coil and you get a really good spark developed at the plugs. The CDI also takes a lower current at low revs so gives better spark when cranking with the starter motor. Superdreams and CX500's moved to CDI but I think the hi voltage to charge the capacitors is derived from an  alternator winding. The Boyer system has been around a long time though so not knocking it.

Cheers ...AshD

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