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rpriest

Yamaha TT500 to XT Conversion

23 posts in this topic

Hey Everybody, I am currently in the process of making my 1977 TT500 into an XT500.

My first question is, is there a way to run a headlight off of the engine or magneto or something?

Second on the XT wiring diagram there are 2 wires coming off the flywheel. On the TT diagram there is only one wire coming off of it.

:excuseme: What are these 2 wires for on the XT diagram coming off of the flywheel?

And wil I need these to do the whole conversion?

Thanks

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On your TT you,ve got 2 wires coming out of the stator the black is ignition as you probablt already know and depending on the year the other wire is RED or RED/WHITE. The red is an AC power wire that can be used to run a headlamp.

On the XT you have the YELLOW and WHITE wires. These wires are basically like the the red on the TT they provide AC power.The white goes to a rectifier to convert AC to DC for battery charging. The yellow wire connects up with a regulator and the headlamp so no matter what the headlamp is on with the engine running and regulates the amount of voltage going to the battery. If you're interested in going 12volt with the XT's 6volt system here's a link to how to wire the XT stator. http://www.norbsa02.freeuk.com/XT500alternator.GIF . I did this conversion with mine seems to work well. I had to modify (actually made a new one) the wiring harness because when you do this all the lights run off the battery. Sounds like you'll be making a harness so it should be no problem to do what you want to it.

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I dont really know the benefit of switching to a 12 volt sytem? But to make sure I got this right, all I have to do is hook the headlight to the red wire coming out of the stator and this will run my headlight whenever the engine is running? How do I do this there is a wiring harness connector on the headlight with what looks like multiple connections.

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The advantages to going 12 volt are bright lights at idle and you can get 12volt bulbs at any parts store. 6 volt stuff is not as common as it used to be. As to your headlamp connector one of the three is ground and the other 2 are high and low beam. Which is which escapes at the moment but it should be pretty easy to figure out by testing the connections with a battery. You should also run some kind of power regulating device i.e. an AC regulator just so you don't blow the bulb when you miss a shift.

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I dont have a battery, but what I want to do is run the light switch and light bulb off of the engine with a voltage regulator in between. Is this possible in a 6V system?

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Yes it is possible with the 6 volt system if you can run down a 6 volt AC regulator. I can't imagine that would be hard to locate. You might want to check the lighting coil with a meter just to see how much AC voltage is available when the engine is at a high idle. You might be able to run a 12 volt headlamp if the 6 volt setup doesn't work out. As you've probably noticed I'm a little hung up on the 12 volt thing. Mainly for parts availabilty and it's just better or brighter lighting. Your idea will work just fine. You only have to be careful how much load you put on the system. 30 or 35 watt headlamp is about all you're going to be able to run and I was told by a reputable stator builder run LEDs everywhere else as they don't draw much amperage and let the headlamp use the power since it draws the most.

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i'm runnin the stock 6v regulator & diode on a 79 xt500

no battery, battery eliminator (big capacitor), stock 6v headlight & 12v LED taillight. no issues. i'm with beezerjoe, 12v is the way to go.

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It is hard to find a voltage regulator for the xt500.

1-Is the diode necessary to keep the current going in one direction?

2-Also with the 6v regulator how can you run 12v led tail light?

3-Is the capacitor there to store the charge that the engine is producing until it is needed by the electrical system?

4-Also can I just switch the 6v light bulb for a 12v bulb or will there not be enough power?

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It is hard to find a voltage regulator for the xt500.

1-Is the diode necessary to keep the current going in one direction?

it converts the ac output to dc

2-Also with the 6v regulator how can you run 12v led tail light?

the voltage is sufficient to run the 12v LED. i tried a 12v 1157 & it didnt work, the 6v bulb works, but also burns out easily. i had an LED bulb already, so i got lucky

3-Is the capacitor there to store the charge that the engine is producing until it is needed by the electrical system?

no, only to replace the load that the battery normally provides. it also smooths out the voltage output

4-Also can I just switch the 6v light bulb for a 12v bulb or will there not be enough power?

it depends on the regulator you have. someone posted a Moose 12V regulator Parts Unlimited # 2112-0090 They are less than $15. will work to convert to 12v system. i plan to try this soon as i score a used 12v halogen for cheap

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it depends on the regulator you have. someone posted a Moose 12V regulator Parts Unlimited # 2112-0090 They are less than $15. will work to convert to 12v system. i plan to try this soon as i score a used 12v halogen for cheap

With the XT I built I used a Tympanium regulator/rectifier that is used to replace the stock charging stuff on an old British motorcycles but I had to float the ground in the XT's stator and made up my own harness for the bike. Charges like a dream. The Tympanium is about $45 and a company called Sparx makes one as well.

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It is hard to find a voltage regulator for the xt500.

1-Is the diode necessary to keep the current going in one direction?

2-Also with the 6v regulator how can you run 12v led tail light?

3-Is the capacitor there to store the charge that the engine is producing until it is needed by the electrical system?

4-Also can I just switch the 6v light bulb for a 12v bulb or will there not be enough power?

1. regulators are abundant. Try companies like Tympanium or Sparx for your regulator. You can check with Trailtech or Baja Designs but since you're working with an old bike don't expect much help with your situation. Rickystator has always had good info and parts. Diode would be necessary if you running a DC system. If you go that route the new solidstate regulator/rectifier units have them built in.

2. If you're going to run a 12volt taillamp why not convert the whole thing to 12volt and get it over with.

3. If you're going to run the light of the engine you'll be doing it with AC current and you won't need a capacitor But I would recommend an AC regulator. If you convert to DC then you will need the capacitor or a battery.

4. If you change the bulbs from 6 to 12 volt units they'll look like a dead flash light with only half the power.

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Awesome you guys are so helpful, thanks. I think I'll just stick with the 6v system and run my light off the engine with a AC regulator.

1-Can the regulator be from any bike that was 6v or does it have to be XT500?

2-Is it possible to run the whole electrical system off of the engine?

3-If not, what is the limit to how much I would want to run off of the engine?

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Awesome you guys are so helpful, thanks. I think I'll just stick with the 6v system and run my light off the engine with a AC regulator.

1-Can the regulator be from any bike that was 6v or does it have to be XT500?

2-Is it possible to run the whole electrical system off of the engine?

3-If not, what is the limit to how much I would want to run off of the engine?

2on mine it is. the only components i use are headlight & tail/ brake light, but i had the gauges on for a time with no problem. the points/ coil/ spark plugs run on a dedicated ignition coil

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2on mine it is. the only components i use are headlight & tail/ brake light, but i had the gauges on for a time with no problem. the points/ coil/ spark plugs run on a dedicated ignition coil

I dont understand how did you seperate the points and plug from the rest of the system?

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how does the brake light switch hook up to the brake pedal?I can get ahold of one but dont really know what to do with it once I have it.

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