TOPIC:

dont flame me yet for this, I did do a few searches and didnt find what I wanted to know


on my 77 kz400 project I want to run without a battery, also planning on not running anything but a tail light, no head light, or turn signals.

basicaly I want to know what kind of wiring is involved to make this cycle run with just a tail light and kill switch ala "dirtbike" ???

Kool, seems like you are setting up a racer.

I know that my 77 650 has no permanent magnets. It needs charge in the battery to generate the generator's field to create more electricity.

Therefore, if the battery is dead, there is nothing I can do to start the system. It needs a little battery charge.

I wonder if A.) Your system is the same. And B.) if an initial charge may be applied (jump started essentially) then removed once the bike is up and running.

I wonder if you could use a mini battery instead. Less weight than a regular sized one, enough juice to initiate the field and a much simpler modification.

Otherwise, I would not know what to do with the leads for the battery. Run the positive lead thru a large resistor to ground? Leave it open? I have no schematic right now, I would wait for a more competent reply than mine.

This thread may help.

HMMM.... SO I will have to have some sort of battery even if its a scooter battery, how is it hooked up? I see what appears to be a large charging wire going to the battery, I guess it stays hooked up and the battery is properly gorunded thats all it takes?? hmm.... maybe I need to pick me up a manual for this machine.

duffis me said no headlight! lol I plan on putting a headlight on it still. Just want to make the wiring as spartin as possable and clean the whole machine up that way.

Well that answers the problem huh?

If you ran without a battery, you would need to put in a large capacitor between the old battery leads.

So it is not going to be a racer. I guess it would be best to use a battery. I still kill my motor from time to time. (who am I kidding, I kill it multiple times a day. My riding skills suck.) No battery means no field charge,.. which means pushing.

It could be done though. Get the smallest of small 12 volt bike batteries and stash it under the seat. You could get used to kick starting it, and compression starting if you can't get it to kick.

Are you still going to run the idiot lights? They are my indicator as to whether or not I have some charge in the battery. I also run a small voltmeter hooked to ignition power on my handlebars. (A leave-over from my days of electrical snafus).

The oil light would be a great voltage indicator. Key on, no oil pressure so the lamp goes on. Life is good. Start the bike, oil pressure builds so the light goes off. Life is even better. Brilliant.

Oh yeah. The manual. Worth its weight in Canadian Bacon and pineapple Pizza. I have mine on my bedstand and can read it like any other book. Get two or three of them. Give it a girl's name. Whatever. Just get one, recommendable definitely.

Does your 77 have a headlight switch? Mine does. It is nice to use when I know my battery is low. If you are going to use a proverbial Duracell on your bike, it would be nice to drop the load as much as possible huh. The lighter the load, the smaller the battery required. As I understand it though, the generator field draws a lot of juice while the motor is not running. So you can't go too small with the battery.

I'm runnin at the mouth.....

Post edited by: Qdude, at: 2008/02/05 11:36

sykolincoln wrote:

HMMM.... SO I will have to have some sort of battery even if its a scooter battery, how is it hooked up? I see what appears to be a large charging wire going to the battery, I guess it stays hooked up and the battery is properly gorunded thats all it takes?? hmm.... maybe I need to pick me up a manual for this machine.

duffis me said no headlight! lol I plan on putting a headlight on it still. Just want to make the wiring as spartin as possable and clean the whole machine up that way.

The battery is the filter componenet of the electrical system that smooths the output from the alternator which is pulsing DC voltage. You can get some hellacious voltage spikes in the system with no battery or filter capacitor, spikes enough to kill electrical components.

well then! thank you graciously for the replies! basicaly I want a head light, a tail light and not worried about electric start, but since I will still have a battery I guess I will keep it. but is there any way to clean up the wiring? there seems to be alot going on for such a sparten bike as far as wiring goes.

ok so has anyone done this?? I would like to see/read everything incolved in doing this, I dont want to start making my own decisions on this and rather follow someone else's plan.

sykolincoln wrote:

ok so has anyone done this?? I would like to see/read everything incolved in doing this, I dont want to start making my own decisions on this and rather follow someone else's plan.

I think one plan might be to get a schematic of the bike's electricals, and use a highlighter to light up the circuits you want to keep.

Then strip out the stuff you don't want and keep what you need.

I remember a long time ago rewiring an old jaguar XK-120 with a pretty crude electrical system. You can do it but it's a time sink.

What you are looking for is called a "total loss ignition". Many companies make them for many bikes. That is what all the racers use. They either bump start the bikes or have a starter cart that turns the bike over. Do a google search and it may help a bit.

I cant start it using the suplied factory kick start if I eliminate the battery?

sykolincoln wrote:

I cant start it using the suplied factory kick start if I eliminate the battery?

There will be no power for the ignition. You need a battery. I recommend a scooter battery from a honda Spree 12v. I've used that successfully on several bikes that couldn't go battery-less.

Here's what the wiring would be like. I drew this for a 76 S2, but yours should be very similar:

The kill switch is optional. You can use the key switch instead of the kill switch. The Key switch is drawn as a generic switch since that's what we used on that bike.

Post edited by: loudhvx, at: 2008/02/07 02:18