Boyer Battery Booster

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In early September, there was a thread in the INOA group from someone who suffered a violent kickback on a Norton with an early Mark 3 Boyer when the battery fell below 10 volts. This reminded me of an idea I posted in 2014 about boosting the battery's voltage with dry cells during starting. I never built it then because I didn't need it, but over the last few weeks I designed and built it for my bike and it works very well.

Here is a series of photos on how it's done, with comments explaining the system and how to use it. Feel free to repost elsewhere if you give me credit.

https://www.flickr.com/photos/miket_nyc/albums/72157699912784351

Mike Taglieri
 
Interesting and simple. Bought 2 D - Cells today for a flashlight that was kaput. Tossed it so still have the new D -Cells.
 
Mike,
How long do you expect the D cells to last....my coils pull about 4amps. Have you considered that the D cells will be tied to the alternator and will be charging the D cells... For some period of time until you switch them out?
The voltmeter shows increase in voltage... Is that with the ignition on or off?
Not sure how safe this is
Rod
 
Could explode in a ball of sparkly flames , yes. Or melt into a blob similar to Chernobyl meltdown. Sparkly bits on a carbon black backdrop . Could charge tourists to view it.
 
Supply to the input of the booster and output of the booster to the Boyer. Doesn't matter if you are positive or negative earth. The negative input and output of the booster are common so if you are positive earth you need to connect the cold side of the coils to the positive output of the booster and not to chassis.

I've used several of these boost regulators (home built) over the years and a couple of these ready made ones recently. Today, I have one on a Rocket 3 with a Madigan starter and a Sparx ignition and one to my CDO as it has an Alton and Boyer and I broke all the Alton shear pins on a very cold day last winter. I have a variable power supply for testing and setting up. Just input about 8V and adjust the potentiometer for a 13V output. As you change the input voltage you can see the regulator always maintains the set output And follows the input voltage when it exceeds the set point. On the bike you can measure the ignition supply when cranking the motor and see that it is below the voltage required for a Boyer with out the regulator and all is good when it is fitted. The symptom I had with the R3 without the regulator is that the engine would fire at the instant you release the starter button I.e. The ignition is not firing when the motor is cranking.
 
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Modern battery and a ride once a month at least would render this mod obsolete. The batteries these days are far better than those of 10 years old and less. I have left my Yuasa for 3 weeks and hit the button and the bike started in the blink of an eye, even in the winter.
Generally, those that still suffer this issue are those who left their bikes 6 months plus and then expect the battery to work without a decent charge - if the battery will still take one.
 
To pdl999: Maybe I'm misunderstanding, but it looks like this booster regulator device you're talking is something that has to be plugged in. I suppose that would do if all your Norton rides start and end near an electrical outlet, but I rather like to go places on my bike. Also, even if this device can run on battery current, flicking a switch is much easier than finding it and plugging it in.

To Torontonian: As I said, I normally test any modification for several months before sharing it, but that was impossible if I wanted to get this out to people for this riding season. But I have tested the voltage of the alkaline batteries occasionally and it does not seem to be changing. Also, no offense, but the idea that running the charging current of the bike through two C batteries for a few seconds is going to make my bike go up in a fireball is just silly.
 
Mike, the device is permanently wired in place on the bike. It passes through the voltage from the battery if it is above the threshold you set and if the battery voltage falls below the threshold, it boosts it to the set voltage.
 
Mike, the device is permanently wired in place on the bike. It passes through the voltage from the battery if it is above the threshold you set and if the battery voltage falls below the threshold, it boosts it to the set voltage.

I see, I misunderstood. So this circuit functions for DC current the way a transformer functions for AC current, raising the voltage to a desired range at the expense of amperage. But when I see a problem on an otherwise very reliable device, I still prefer to fix it with home-grown devices than buy a gadget to add to it. To each his own.
 
Alternatively fit a pazon altair. On my bike with original electrics, meaning two phase alternator, original rectifier and old rotor, it starts even without battery in one or two kicks. No kickbacks whatsoever.
 
To pdl999: Maybe I'm misunderstanding, but it looks like this booster regulator device you're talking is something that has to be plugged in. I suppose that would do if all your Norton rides start and end near an electrical outlet, but I rather like to go places on my bike. Also, even if this device can run on battery current, flicking a switch is much easier than finding it and plugging it in.

To Torontonian: As I said, I normally test any modification for several months before sharing it, but that was impossible if I wanted to get this out to people for this riding season. But I have tested the voltage of the alkaline batteries occasionally and it does not seem to be changing. Also, no offense, but the idea that running the charging current of the bike through two C batteries for a few seconds is going to make my bike go up in a fireball is just silly.
Simply silly humour on my part M. as some on this forum are wound up a bit too tightly and need pressure relief valves. I already have one of these Capacitor panel boards in hand and will install it inline this winter. Obviously it will need a small box fabricated to keep out moisture. The price was right. Enjoy.
 
Alternatively fit a pazon altair. On my bike with original electrics, meaning two phase alternator, original rectifier and old rotor, it starts even without battery in one or two kicks. No kickbacks whatsoever.

I'm sure the Pazon works fine, but a new one is $130 on eBay. A new Boyer Mark 4 is about the same, and there are other alternatives too, and I suppose there's lots of discussion over which is best.

But that's not the group I designed this circuit for. It's for people like me who already own Mark 3 Boyers and are happy with them except for the kickback problem when the battery is weak or is pulled down by an electric starter. These old Boyers otherwise work fine and are very affordable. I bought a spare one (which I've never needed) for about $30.

If you're on a budget, my added circuit also costs about $5 for the switch, battery holder, and batteries. MUCH cheaper then any of these other alternatives.

Mike Taglieri
 
Mike, The Mike Taglieri of headsteady fame ? well welcome!

Let me get this straight, so before starting you change the Boyer / coils to the "D" cell supply, spin up the engine and once started switch back to alternator power? If so that seems a very pragmatic approach, and the D cells are quickly isolated from any charging. One suggestion however would it not be better to use a single PP9 ( rectangular) 9v battery as they have a simple secure cap connection - i.e only two connection points and be less prone to vibration?

If you look at the price of the voltage regulator pdl999 suggests though long term it will work out cheaper than replacing batteries annually.

To me both have there merits.

cheers,

cliffa.
 
Mike, The Mike Taglieri of headsteady fame ? well welcome!

Let me get this straight, so before starting you change the Boyer / coils to the "D" cell supply, spin up the engine and once started switch back to alternator power? If so that seems a very pragmatic approach, and the D cells are quickly isolated from any charging. One suggestion however would it not be better to use a single PP9 ( rectangular) 9v battery as they have a simple secure cap connection - i.e only two connection points and be less prone to vibration?

If you look at the price of the voltage regulator pdl999 suggests though long term it will work out cheaper than replacing batteries annually.

To me both have there merits.

cheers,

cliffa.
9 Volt dry cells are great. A survivalist friend of mine taught me to spark up a campfire with one. Brush a scour pad / Brillo across the terminals to create serious sparkage to light up a campfire.
 
Boyer MK3 is no longer supplied, the digital kit is now supplied instead and the price is much the same as the old MK3 analogue kit. Also, maybe me but not many seem to use the Boyer MK3 these days.

If anyone is suffering battery voltage drop after a month, then get a modern battery as they hold up far longer than the older style batteries. I have left my MK3 for 3 weeks and it flashed up first hit of the button. If your battery has been left any longer - maintain it with a charge.

Any sort of additional kit is surely delaying the inevitable.
 
Boyer MK3 is no longer supplied, the digital kit is now supplied instead and the price is much the same as the old MK3 analogue kit.

The Boyer MkIV isn't digital.

http://www.boyerbransden.com/micromarkiv.html
"The Boyer Bransden range of Analogue MKIII ignition units are being progressively changed to improved MKIV versions. The changes 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. All Digital and Power designs will remain as before."
 
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