Ironhead rewire sans Battery

Howdy!.....I have a 1964 ironhead sportster with magneto ignition. I want to rewire it without a battery, just using the generator and a reg rectifier I just want high /low headlight...stop/ rear lamp...Does any one know the easiest way to do it??? also is there an easy way to test the regulator /rectifier...it currently has an evolution type one on but the bulbs keep blowing...so I think it may be junk...Can any one help...I wanna get it done after Christmas....Thanks and Merry Christmas...Andy

[the_french_owl]

Hi Andy,

I don't think you can use an electronic rectifier with a no-battery CH.

These old CH were fitted with a relay rectifier set on a lower voltage, that's why you're blowing lamps...

Std battery XLH setting for the relay rectifier was 6.7 volts. For a CH, it has to be no more than 6.3 volts.

The other battery relay rectifier was a Bosch, 12 volts, from 66 or so.

That can be reset lower by an old auto electrician if you know one... they're getting fewer on the ground sadly...

Patrick

Hi Patrick, I have one of those bosch rectifiers in my box of bits , its off an ironhead 65 sportster xlh, would I be able to use that ??? Its got 3 or 4 terminals on it ...and it definately works....Andy

[the_french_owl]

Yes, you can use it if your lamps and gene are 12 volts but it will have to be set a bit lower... or you will blow your lamps with monotoneous monotony...

Patrick

[bazereid]

Back in the 70s and 80s when I used to eat sleep and breathe Norton Commando`s (until I discovered the mighty Harley), I was sometimes forced to run one occasionally without the battery. This was possible because Norton had the rare foresight to fit a large capacitor in the circuit which stored enough energy after a few lunges on the kickstart to power the ignition coils. Thereafter once the motor was running absorbing enough of the output from the generator to prevent it burning out. This system also required a zener diode to dump excess charge with or without a battery, a standard set up on all 12 volt Lucas systems on Brit bikes. There is no reason why this could not be used on your bike if you run it at 12volts.

Type 2MC capacitor may be available from the Norvil Motorcycle Company, they may well have an improved alternative by now.

There are also other battery eliminator products in existence, but I cant remember off hand who produces them. Soon as I find out I will let you know. PM me if you ever require more details on how to wire it up etc.

[the_french_owl]

Thanks for reminding me, Barry, as you know, I'm not running bikes with lights..

Indeed, the Bosch regulator on 66 to 69 batteryless CH does have a capacitor fitted!!! That might be enough to supress surges and blown lamps.

Patrick

[chilly]

Maybe "Boyer Bransden" can help,i've got a Commando that i was running without a battery with the help of a little black box from Boyer,it was set up a bit different from Barries tho, with no Capaciter and Zenors which apparently are difficult to get as matched pairs now,you need 2.

Google= boyer bransden

Plenty of info on there,they also have a help line between 4 and 5pm very helpfull people.

Good luck

Chill

[Kiwi]

time to invest in easyriders publication tips and tricks vol 1

it has the wiring diagram you need

volumes 2-4 are also a wise investment in useful knowledge

Well thanks you Guys , theres enough info to start me off. The bikes got a magneto to provide power for the engine just need to wire upto the generator to provide the right amount of juice for the illumination...can I use a squeezy horn or do I need an electric horn for the mot? I will try and source a 66 up bosch reg/rec that sounds like it could be right for the job...
how do I get hold of the easy rider hints and tips book? that sounds like a wealth of info...which is always handy!!!
Have a good Christmas And all the best for the New Year!!! and thanks again ...Andy

[panheadpete]

I've read and re-read this thread and I'm puzzled now; then again, it's not unusual...Electrics fascinate me but my knowledge is , shall we say, less than complete! The bike being discussed has a 6V generator, yes? That puts out DC, so any form of rectifier (converting AC to DC) is not needed; just a voltage control, again, my limited understanding of electrics tells me that a battery is necessary in any DC generator (dynamo) system, yet Patrick refers to a battery-less system above. Does the capacitor replace the battery? If so, that sounds like the perfect answer.