another annoying electronics question:

As my name implies, the 71 basket case had wiring that was kaput, so I'm starting from scratch: I'm keeping things simple with headlight/taillight/brake light, horn and kill switch.......

as far as I can tell, I'm going to need a boyer analog unit along with my 2 phase stock alternator/rotor. I'll probably go battery free so I'll need the blue capacitor. I'll use a twin lead coil and do the whole bike 12v with neg ground so I can use Japanese switch cluster on the bars

I figure I'll use a more modern power module: so my question(s) are:

1. which power module? the boyer or podtronics ?
2. what am I missing for electronic components?

keep in mind the bike will be noodling around northern new england and not a competition /hi performance thing.......

as always, thanks for putting up with the newbie questions.

sincerely:

Karl hoyt

Battery

Hi Karl,
I question your decision to go battery-less. There may come a time when you need headlight, tailight, brakelight, directional, and maybe even the horn to be operating at the same time. Without the stored energy of a battery you may find your electrical system lacking enough output to take care of all your needs.
Yuasa sealed batteries are clean and small, available in 7, 9, or 12 amp versions which should fit easily in a Commando.
BTW +or- ground the Japanese switches don't care which way the current runs through them.
justa thought,
G.B.

Karl,
I agree with G.B. Keep the battery. If you are just "noodling" the Boyer will not be happy with the stock alternator output. I have a small sealed 12 volt emergency lighting battery that I plan to try out next riding season. A couple people I know swear by them. No acid worries and small enough to use most of the battery box for storage or to mount your electronic voltage regulator.

If you insist on going battery-less, then at least replace the alternator with a three-phase Lucas or Sparx. This will give more juice at lower rpm than the stock or replacement single phase.

As far as an electronic regulator/rectifier, I have used Typanium and Podtronics, but have no experience with the Boyer or Sparx units. I haven't heard anything bad about any of them. The Typanium is the smallest and can be hidden away easier, but needs to be mounted on a heat sink. The others are somewhat larger because they are encased in aluminum to help dissipate heat.

Since you are doing the electrical from scratch, I have two other words of advice. 1) Use a small fusebox with blade fuses and give lights, horn, and ignition separate, fused circuits. 2) Use relays to energize the headlight, horn, and Boyer. Don't route primary power thru the keyswitch and handlebar switches. You'll get a brighter headlight, a reliable horn, and the Boyer will see the constant 12 volts it likes to keep the plugs firing.

Thanks to Ron and GB:

excellent feedback: thanks.

The no battery 'decision' wasn't so much a decision as a reaction to earlier posts from other members. I think that I'll go with the battery because, as you say, GB, there may in fact be times when I'm going to want to be sitting on the side of a twisty New Hampshire road and want to be seen by oncoming vehicles. Info regarding having a small fuse panel for all the components is wise advice which i will take. I had already decided to do this and wire everything point to point, so there's no funky bullet connectors to fritz out on the road ( I AM an experienced Brit bike rider )

I forgot to tell y'all that I'm also adding an accessory jack so I can wire in an I'pod through a 1000 watt power amp so I can blast snoop dog as I drive around .

just kidding on the snoop thing. The Miles davis quintet (the ron carter herbie hancock years) maybe, but not ol snoop

thanks again and happy holidays I'll submit before and after pix of the basketcase as the build progresses. This month: a cobalt blue paint job!

kfh

Ron L said:

Since you are doing the electrical from scratch, I have two other words of advice. 1) Use a small fusebox with blade fuses and give lights, horn, and ignition separate, fused circuits. 2) Use relays to energize the headlight, horn, and Boyer. Don't route primary power thru the keyswitch and handlebar switches. You'll get a brighter headlight, a reliable horn, and the Boyer will see the constant 12 volts it likes to keep the plugs firing.

Click to expand...

Ron
I'd be interested to know where you located the fuses and relays on your bike as I'm rewiring my Commando in a similar way. Any chance of a posting a picture or two?

=======
Tim

Tim,
When Jerry gets the photo section done I can try to post some pictures. I did this somewhat piecemeal on my Interstate and need to clean up some more of the wiring. My Interstate is a little different than most because I have a cable operated rear master cylinder mounted on the flat frame plate where the old selenium rectifier was. (using a MkIII rear disc with left side brake and right side shift). Basically I made a small aluminum mount inside the battery box to which I mounted the Podtronics regulator/rectifier and a small four circuit fuse panel. The panel is the type that takes a common feed, then separates it to four fused circuits. I used Bosch type relays and mounted the lighting one in the headlight shell and the horn and ignition near the battery box. The next time I would try to mount the Podtronics on the flat frame plate behind the battery box. This should make more room in the battery box for the fuse panel. Since I have a three phase 180 watt Lucas alternator, I picked up a small sealed emergency lighting battery to try out. I won't get to that until after Daytona, but it should give me a little more room in the battery box and I may have to re-design my aluminum mount.

thanks for the feedback, Ron: I'm not familiar with relays (I'm a psychologist turned guitar builder and woodworking teacher) . what is their function and are they something I could get at a decent pro-quality auto parts store?

thanks

kfh

A relay is a device that switches current that is too high for the handlebar switch to deal with.

Horns and headlights draw a fair bit of current so that's what they are used for on bikes....and starter motors if you have a Mk3.
You can get them at any decent auto store.

And to add to Pommie John's explanation, if you are using a Boyer, they are sensitive to voltage, so the fewer Lucas switches the power goes through to get to the black box, the better. For my set-up the power goes from the battery to the relay to the Boyer. The relay trigger circuit goes from the battery through the keyswitch, through the handlebar kill switch to the relay. The contacts in the relay are sealed much better than those in the key switch and the handlebar switch, so there is much less current/voltage loss. The trigger circuit is much less sensitive to voltage loss, assuring that the ignition receives all the voltage it needs despite the condition of the Lucas switches.

thanks to all: this is a thread I will definitely put in the 'save' box for future reference. I won't be doing any wiring until probably march, so having this as a reference will be very helpful:

seeya at the auto parts store 8)

and for all those so affected, Merry Christmas and Happy Channukah

karl