Setting up battery on dirt bike

Hi, i recently got around to restoring a 98 yamaha rt 180. I have a headlight i am interested in installing on and i know the bike has a lighting coil. I am guessing the coil will be pretty weak so i have come up with an idea. From here, it is not model specific. I made room for a battery when i decided to junk the airbox. So i want to set this up with a battery and i plan to use a regulator rectifier to have the lighting coil charge it. I am pretty sure everything will work, but if i pick up a 12v regulator off another bike i am unsure of how to wire it. It seems there are 5 wires coming off of the regulator i am looking at and i need to know where those go before installing everything. Would this work? It seems to be a cheap option.



That regulator you're looking at must be on ebay as I looked for mpgstore.  I thought about going that route but ended up getting a Bajadesigns unit.  What you're looking at could work but since it's got 5 wires that would lead me to believe it's for bikes with 3 phase alternators which I've never seen on small bikes.  You could contact the vendor and ask him what the function of all the wires are.  

I searched on ebay for universal motorcycle regulator rectifier and came up with several with 4 pins for $6 from China.  That would should work for bikes with single phase alternators.  

But I just looked at pictures of RT 180s and I don't see lights on them so probably it doesn't have a lighting coil.  But you say it does.  Are you sure? 

I looked on the parts diagram and it showed one.  If so, there should be a couple wires coming out that are not connected.  

Edited by flyandride

Thanks for a little insight that should help.

So if that regulator has 4 wires then how would i go about wiring that

That's the one I would get.  You'll still have to find out the wire functions, the seller should be able to tell you that.  2 of the wires would go to the stator, the other 2 would be positive and negative. 

Steahly also has a regulator made for bikes with batteries.  Probably not as cheap as Chinese....

If the lighting coil is as weak as you say, it will not have the juice to charge a 12v battery with the light on, which kinda defeats the purpose of using a battery.

You can run the headlight without a lighting coil on a battery, or just run the headlight off the coil without a battery. Unless you upgrade the coil, it won't charge the battery.

My wr250 has a 35w coil and it is bit enough power to charge a battery and run lights, for reference

Well, about 90% of the time i dont need lights on

Sounds like you should use a small battery to run the lights you do need, then run ONLY the headlight of AC power to it gets the full power from the lighting coil.


Use LED lights and you will get several hours out of the other lights. Be sure to use a switch so that you can turn them off when not needed.

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