General wiring questions....

[sclay115]

Working on a CB350 twin, and what strikes me as the most abnormal is the complete lack of fuses(save one) and the lack of relays(I'm used to the automotive world). My concern is that the headlight is basically hardwired into the same circuit as the ignition system, same of course with the taillight. With no fuses, wacky. But I'm under the assumption that Honda did a little engineering and this is ok if I wire it the same right?

And I've heard that you need to jump some wires if you are to run the headlight at all times. And I think I have figured out which it is. But just to clarify, it is a white wire out of the alternator, and the yellow wire going into the rectifier that I need to connect right? I am 95% sure that is it, but just figured I would ask.

Thanks folks!

Steve

 

[DrJ]

Yes, the CB350 and the other vintage twins have relatively simple wiring with the single fuse. But that doesn't mean you can't place a fuse along the headlight circuit if you wish to. But I wouldn't modify the electrical too much unless you are an expert. The old Hondas have notoriously weak charging systems. If you wire the headlight to stay on, make sure you compensate by wiring the stator to charge on all fields or else you constantly drain the battery. I personally wouldn't do this, I like having a headlight switch.

 

[sclay115]

Yes, the CB350 and the other vintage twins have relatively simple wiring with the single fuse. But that doesn't mean you can't place a fuse along the headlight circuit if you wish to. But I wouldn't modify the electrical too much unless you are an expert. The old Hondas have notoriously weak charging systems. If you wire the headlight to stay on, make sure you compensate by wiring the stator to charge on all fields or else you constantly drain the battery. I personally wouldn't do this, I like having a headlight switch.

DrJ, Normally I'd do the same, stick with the switch and such, but I don't have an original piece, and I probably wouldn't end up using the 'off' position very much. And my automotive background leads me to ridiculously overthink this system, when in reality it really is just that simple, sorta strange, I tend to do this pretty frequently. But as for the wiring modification, just to clarify, are we talking about connecting the white wire out of the alternator to the yellow wiring coming out of the rectifier? Picture for reference:

Steve

 

[sclay115]

Also, one more thing, had a question about the ignition switch itself, three positions. Off(obviously), 1,2.

Position 1 has the ignition system on, running lights, everything to have the bike ridable.

Position 2 seems to have all the same attributes, but, I am able to remove the key, I cannot do this in position 1.

Is this correct? I know most modern cycles have a 'parking' mode, that leaves the lights on, but kills the ignition, never could figure out what it's used for, but know it exists. I would have though #2 would be this. This might actually be really convenient for me, as I could turn the ignition on, remove my key, and never, ever worry about it coming out of the cylinder and being lost on the road. But just wanted to see if this was similar to anyone else's switch...

Steve

 

[DrJ]

Also, one more thing, had a question about the ignition switch itself, three positions. Off(obviously), 1,2.

Position 1 has the ignition system on, running lights, everything to have the bike ridable.

Position 2 seems to have all the same attributes, but, I am able to remove the key, I cannot do this in position 1.

Is this correct? I know most modern cycles have a 'parking' mode, that leaves the lights on, but kills the ignition, never could figure out what it's used for, but know it exists. I would have though #2 would be this. This might actually be really convenient for me, as I could turn the ignition on, remove my key, and never, ever worry about it coming out of the cylinder and being lost on the road. But just wanted to see if this was similar to anyone else's switch...

Steve

Position 1 is the running position, everything is on and key is locked in so it won't fall out during riding.

Position 2 is the park/emergency position and only the tail light should be operating. Key is removeable in case you need to leave bike but want it visible. You shouldn't be able to run the bike in this positio.

And about wiring the headlight to be on at all times and compensating at the stator, that's above my head. I'm not enough of an expert to guide you through that mod. But if you succeed, please post results.

 

[chrisf]

I run a headlight full time and use 3 extremely small batteries. Like you, I was concerned about the lack of relays. I don't use a key on my bike. Instead, I use a hidden toggle switch that energizes a relay. That relay powers the entire system. I have one 30A fuse that goes between the batteries and the relay.

Like I said, the headlight is hard wired. When the toggle energizes the system, the headlight comes on. I have a small toggle on the headlight itself that energizes the highbeam. The toggle was cheap, so if it burns out, I'll just replace it. Plus, I really don't use it.

For the charging system, DrJ is right. In fact, he helped me through my struggles. For some ridiculous reason, Honda used a half-charged mode and a full charged mode. WTF knows why. I initially isolated the white wire coming out of the stator/generator. This would allow me to ride for a 1/2 mile or so, then die--I was essentially running on the small batteries. The trick is to wire the yellow wire AND the white wire from the stator to the yellow wire on the rectifier and regulator. NOTE THAT THIS WORKED FOR ME so please don't get pissed if something blows up or the wiring harness burns down. I used a 100% custom wiring harness that I built. I also used a solid state rectifier, not the wierd-looking solenium rectifier.

Below is my wiring diagram, only my white wire connects to the yellow wires. Please use at your own risk.

--Chris