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Hi Guys

I’ve had my Boyer Bransden kit arrive today and attempted to fit. It say us coil 0008 but came with 2 0007 coils which are reference in the instructions for Brit Bikes. Anyone else had this or should I be using them.

Tank doesnt fit with them on so making me think the wrong ones are in the box. KIT 000293

https://www.britishbikebits.com/boyer-micro-power-igntion-kit-honda-cl-cb-250-350

Instructions below.

https://burtonbikebits.net/bbb/wp-content/uploads/2016/09/KIT00293.pdf

Any advice appreciated. So close to getting this thing finished.
 

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Hi.
Just fitted my Boyer kit. It came with two seperate coils, can't reference the type as are fitted but if needs be can take the tank off and check.
I fitted my pair of coils using the front mounting bolt and stand off spacers rather than the old coil bracket. All fits easily with plenty of room. BTW, I put the Micro box into the open top of the frame spine, suitably protected with a foam packing. Keeps the igniter box away from coils induced interference but does require some cable lengthening.
I'll get some pics up in an hour or so.
 

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Works fine, just done a 100 mile run, in some pretty inclement weather too.
Must admit, I had to do some thinking about the pick up coils but, as Bransden quote, it sparks every TDC, one of which is the exhaust stroke so is 'wasted'. I presume its to balance the rotor mass. Pity, as it will put an extra drain on the electrical supply. The difference in spark intensity is very obvious, a bright blue crack even when hand cranking the motor round.
 

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Works fine, just done a 100 mile run, in some pretty inclement weather too.
Must admit, I had to do some thinking about the pick up coils but, as Bransden quote, it sparks every TDC, one of which is the exhaust stroke so is 'wasted'. I presume its to balance the rotor mass. Pity, as it will put an extra drain on the electrical supply. The difference in spark intensity is very obvious, a bright blue crack even when hand cranking the motor round.
So your bike is a 175? (you didn't say and it isn't in your signature) The OP was talking about a CL350, which is a 180° crankshaft, and probably why Sonreir commented about the pickup positioning
 

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CB350K2. It certainly works so the pickups must be arranged correctly. I think they operate consectively rather than as opposites. I did note that the coils are wired with a positive connection from the control module to one coil and the other input to the negative of the opposite cylinder coil. Why I am not to sure about, but I will investigate next time the tank is off and take some photos. If I can squeeze the time tomorrow I'll do that.
 

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We talked about wasted spark on the 180° / 540° engines a couple years ago. The wasted spark, I believe, fires into the intake stroke, not the exhaust stroke on the off-cylinder. There are a couple of threads, but I think THIS ONE references the other one as well.
 

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I'm unsure if this method was used, but there are ways that pick-up positioning could work in a 180 engine.......
Think poles of the magnets, and/or diodes to control which way the pulse CAN go so it triggers the appropriate coil.......
Essentially, there is only one pickup as they are wired in series......When two magnets "wipe" past the pickup coil they generate one direction of current flow which is ONLY allowed to proceed to the correct ignition coil trigger by the diodes....When the pickup is affected/influenced by the opposite magnetic polarity, the current is generated in the reverse directionality and likewise sent on appropriately by the other directionality diode to trigger the second ignition coil.....
We use this same/similar diode set-up to separate the "sides" when using a common indicator with LED turn-signals........

Since there are four magnets set at 90 degrees apart (like the stock points are), the pulses occur every 90 CAM degrees, but each ignition coil is only affected by/triggered during every other pulse, (so 180 cam degrees or 360 crank degrees, hence firing on both compression and exhaust)... The other ignition coil is staggered 180 crank degrees apart by the 90 CAM degree spacing.....
 

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66Sprint, I think you have nailed it. I had thought that the rotor magnets might be polarised N/S S/N to give much the same effect. However the pickups are phased, it all works perfectly, very pleased with mine.
 
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