Does anyone know how to wire a 71 commando 750 to run? I just need the basic wiring diagram for the bike to run. Im going to do the lights later on but just need the bike to start for now. I have a Tympathium and a Boyer already on the bike, It was running yesterday but the wiring was soooo bad I had to redo it, im almost done but its not getting any power to the coils when I try to kick start it. I also have a blue cylinder that i dont know what it does but was wired on before I messed with it. here are some pics. If anyone can give me good directions on how to wire just the bike to run and it works i have a $100 check for you. thanks

Have a look at Old Britt's site.

http://www.oldbritts.com/ob_start.html

Look under "Technical Articles" and then "Electrical" (i.e. scroll down the page). There are several basic wiring diagrams for various coils and rectifier configurations.

The blue thingy you refer to was (probably) your MC2 starting capacitor. Argueably, it isn't required with a good battery and is very likely dead from old age anyway.

It's a bit difficult to diagnose/rewire a bike on line with two pictures but..... You can check power to the coils by laying the plugs on the head (connected to the coils),turning on the ignition, and touching together the black/yellow and black/white wires going into the Boyer. There should be spark at both plugs. The power to the coils comes from the Boyer box which gets it's power from the white wire which should connect to the ignition switch. I would start by checking the switch to ensure that power is getting thru it (they often make bad connections due to dirt in the switch itself). If that's ok, I'd go back and be sure that all the connectors (especially the "colored" ones that were added with the Boyer install or as repairs) are good. If it ran yesterday, it's probably wired right, something just came loose and you need to find it.
The blue thing is a large capacitor that originally allowed the bike to run without a battery but that ability goes away with the Boyer installation. Hope that helps

1) battery FULLY charged
2) unbroken fuse
3) battery terminal connections are tight
4) boyer power box is solidly grounded to negative batter
5) good, solid engine to frame ground is in place verified
6) plugs are good and gapped
7) you have power forward of the ignition switch, your headlight works, etc

9)
10)
11)

sidreilley wrote: If it ran yesterday, it's probably wired right, something just came loose and you need to find it.

what i meant to say was that it ran yesterday with the old rat nest wire harness, then I took it off and re did it today and now its not running.

Corona850 wrote:Have a look at Old Britt's site.

http://www.oldbritts.com/ob_start.html

Look under "Technical Articles" and then "Electrical" (i.e. scroll down the page). There are several basic wiring diagrams for various coils and rectifier configurations.

The blue thingy you refer to was (probably) your MC2 starting capacitor. Argueably, it isn't required with a good battery and is very likely dead from old age anyway.

I agree this is a good starting reference and as mentioned, is the battery fully charged. A quick search I found this recent thread.
post42532.html?hilit=wiring%20diagram#p42532

I remember another thread where the author, drew a diagram in sections as he completed them.

You will be well paid if you take the time to learn the power pathway from the battery through the key switch to all the the pieces that need the power and each pathway back to ground for those pieces. Without this discipline embedded in your ability list you will flounder no matter the pictures. Some time spent with a diagram following the power talking it through with a good friend and some beers ought to do the deed.

Try this thread, you will find some very useful information.
http://www.accessnorton.com/post42526.html#p42526

norbsa48503 wrote:You will be well paid if you take the time to learn the power pathway from the battery through the key switch to all the the pieces that need the power and each pathway back to ground for those pieces. Without this discipline embedded in your ability list you will flounder no matter the pictures. Some time spent with a diagram following the power talking it through with a good friend and some beers ought to do the deed.

I know, I wish I knew more about electrical systems, I can tear down just about anything and rebuild it , yesterday I caught my bsa battery on fire and melted the wires! I blew 5 fuzes too! me and electrical stuff just dosnt mix! Cookie actualy is coming over tomorrow and helping me re-wire it. I just need the simple wires for it to run.

It's great when forum members live nearby and can share in rides, wrenching sessions, cook-outs, etc.

I'm at least 150 miles from the next nearest forum member, if anyone is in Corpus Christi or San Antonio, TX, 240 if Austin, 300 if Houston, and so on...

We got him set up with a basic wiring scheme today. I suggested he use a circuit breaker and redo the wires with proper connectors and in the right colors. I love that little Tympanium box, so easy to wire up.