Power consumption, E-ignition vs Points. also - spare advance cam?

[Skoti]

If tinkering is your thing then Uwe Gottwald at Accent Electronic in Germany does a system whereby you can program the advance curve via a laptop.

He speaks good English and is very helpful.

[McCabe-Thiele (Ted)]

Overthinking I suspect is the norm for members here "act in haste repent at leisure" springs to mind as the alternative.

[AshimotoK0]

I have been an electronics design engineer for yonks  but all of my bikes apart from my 400F (which came with Boyer Bransden Mk3 when I bought it in 1985 and still works OK) will be fitted with the standard arrangement. I think it depends on how many miles you will be covering... not a lot in the case of most classic bikes. The standard ' Kettering' ignition system on these bikes works well ...so if it's not broken ... blah blah. When I got my 1st 400F in 1978 I designed a CDi which used the standard points and did over 20k miles with it fitted (with a couple of popped main capacitors along the way ... capacitor technology then was not really designed for CDi only valve colour TV's). I never changed the points and there was never any significant  wear on the heel of the contact breakers, so the timing never went out. This was with either ND or Hitachi points though ... heard nasty stories about Daiichi points/condensers but that may be that there are lots of Chinese ripoffs around.

So if you are only doing relatively low miles and you can find  decent quality, preferrably OEM points and condensers, then I would fit the standard system. One DS system I saw has the electronics on a circular PCB that replaces the points plate. Irrespective of if it functions OK it only looks to have rudimentary weather/vibration protection and that would really put me off.

I think the original Boyer system possibly draws more current than standard due to it's unique (and patented IIRC) design.
My CDi system used an inverter which drew low current at low revs and higher current at high revs. This is the revers on the standard system.

Oddjob swore by the Hondaman ignition which basically does what my CDi did but just utilises transistors to switch the coil current rather than through the contact points rat. Mine whacked 400VDC across the coil from a charged capacitor... which is what Honda did on the CX500/Superdream etc. etc. ... Like my CDi, with the Hondaman ignition, you can simply revert to the standard setup with a switch because both use the standard points and auto-advancer.

[Laverda Dave]

The problem I always have fitting a Boyer on a 400/4 (and other bikes) is where do you put the CDI unit! On one of them I placed it in the tool holder tray which made it a pia when removing the tray because the cable came through it and on another I placed it on the inside of the side panel with velcro.

[AshimotoK0]

I need to investigate that Dave as mine was just flopping about when I bought the bike. I took one of those Boyer units apart that a member here kindly gave me. Interesting design and it was patented by Ernie Bransden I think. From memory it uses a wasted spark system so doesn't have two switching transistors for each of the two Honda Four coils. So I guess the current draw must be higher than the standard points setup. Really need to revisit it in case I am talking BS plus design some kind of holder for the potted block. Tell you something though, that system seems to have stood the test of time.The failed unit a member (John Webley IIRC) donated to me had failed after many years and miles of reliable service. Plus it was only a failed capacitor IIRC not the main switching transistor.

[Laverda Dave]

On my original 400/4 I zip tied the box on the top frame tube and just clear of the carb bank as there was just enough room for it to sit between the fuel tank tunnel and the frame tube. I thought I'd had a result until one day when giving the bike a handful it topped out at 110mph🙄, (actually it was about 70!). The CDI box had slowly worked it's way back down the frame just enough to interfere with the top of the carbs at full throttle.
I'm 90% sure the Boyer does use a wasted spark Ash👍

[Bryanj]

Boyer fire all the plugs all the time

[K2-K6]

Thats my understanding too ... obviously two pickup though to give the 180 degree timing point.