1985 250R and 1986 Tecate 3 owner here! Also a pristine 87 Fourtrax!

[bryank30]

Just wanted to reach out and say hello! I'm trying to figure out lights on my T3. Currently trying to use a old 250r voltage regulator. Any tips?

Bryan

[Aulbaugh]

Welcome to the site Bryan! I think we chatted on the phone a couple weeks back. We like pictures here!!!

[ps2fixer]

First welcome to 3ww.

Question I have is why do you want a voltage regulator? Are you trying to run LED lights, lower wattage than stock lights or what? Stock there is no voltage regulator, the lights use up all the power the alternator puts out. Here's a wire diagram for 85-86 tecate. If you want to run a voltage regulator, from memory it should go from power to ground, so yellow or red wire to black/frame ground.

Looks like the machine uses a total of 58w for the lighting, more wattage isn't a big deal if it's just a little bit, lower will be a problem with out a voltage regulator (bulbs instant blow, or have shorter life depending how much different it is).

Good luck with the build.

https://i.gyazo.com/d9de4ec7809d9cb9b03cd48f1b178c3f.png

[bryank30]

Wow. Thank you for your well thought out reply. Awesome!!! Ok. I've been blowing my test lights bulb when I rev up the throttle. The bulb in that test light was 28 years old. So I thought something was wrong maybe the bigger headlight and taillight can handle it.

[bryank30]

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[bryank30]

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[Aulbaugh]

Nice looking rides!

[ps2fixer]

Yea how the system works is if there's a low load (say just a tail light, or your test light), it increases in voltage a lot since there's nothing to sink the extra power to which is all the old school voltage regulators did. If you get ~60w of load on it, then the max voltage should be somewhere acceptable like 14v. Test lights are good enough to say if there's power, but for real diag work, a multi meter generally is better because it can give real numbers instead of "dim" or "bright" light. Sounds like your alternator is working well =).

Also for the machines like the 350x (and I'm guessing the 250r with out looking it up), if you leave the voltage regulator out of it, it will do the exact same thing, except the alternator puts out more power than the bulbs can take, so a rev up blows all your lights. I did that exact thing a week or so ago testing a reproduction 350x harness and forgot to hook up the regulator, when I tested the lights I blew them all out at high idle lol.

A voltage regulator wouldn't hurt anything, you could upgrade to a higher output alternator down the road and not have issues, and if you ever have one of your bulbs blow, it will protect the rest from going at the same time.

[ironchop]

I've used these Tympanium Regulator/rectifiers on British street bikes and ATVs like my 85 ATC200X I converted to run a battery and LED lights.

Great little units. Easy instructions included. Never had a bad one in thirty years.

Sent from my Z958 using Tapatalk
https://uploads.tapatalk-cdn.com/20180323/4bc6dde2892dbc927d85193e75721adc.jpg

[ps2fixer]

Does that part support AC and DC? Like the 350x is AC, the Tecate might be DC, I'm not sure. Based on the wiring, it works with a single field (single phase I guess) alternator, a 3 phase one would require a different regulator, but then again those really only show up when the machine has a stock voltage regulator.

[fieldy]

Were you the man making the Tecate harnesses? I didn't see any last time i checked 3ww shop.

[ps2fixer]

Yep, I'm "the wire harness guy" lol. The only Kawasaki harness in there atm is the 84-85 Tecate harness. Not sure why it didn't come up for you, I tried a few searches and it came up for me. It's probably been listed for about 2 weeks so that might be why.

[bryank30]

Ok. Well I just blew the headlight bulb in less than 3 minutes. I was running power through a old 86 250r voltage regulator. Either the voltage regulator is bad or its not made for the Tecate electrical system. Also, I'm sure that stator on the tecate is a aftermarket stator, what are the chances its the original 86? Not much. Ricky stator says you must use a voltage regulator with there stators.

Bryan

[bryank30]

New Hot Shot Kawasaki Stator 21_705H
Description
Reviews
Applications
New Hot Shot Kawasaki Stator: This high output stator has an additional lighting coil with an output of 80 watts. So this is what I'm working with. So could I just buy a used regulator off ebay ? I'm all about being frugal.

[bryank30]

Found this on Ebay for 10 dollars shipped. As long as its 12 volts it should do the job right? Part # 66V-81960-00-00

Yamaha fitting chart shows this is original on the following models.

2000 XR1800 - XRT1200Y ELECTRICAL 1
2001 XR1800 - XRT1200Z ELECTRICAL 1
1999 WAVE RUNNER XL1200 LTD - XA1200X ELECTRICAL 1
2000 GP1200 - GP1200AY ELECTRICAL 1
2000 WAVERUNNER (Metallic Marine Silver) - XL1200Y ELECTRICAL 1
2000 XL1200 LTD - XA1200Y ELECTRICAL 1
2001 GP1200R - GP1200AZ ELECTRICAL 1
2001 XLT1200 - XA1200AZ ELECTRICAL 1
2002 GP1200 - GP1200AA ELECTRICAL 1
2002 WAVE RUNNER GP1200R - GP1200ACA ELECTRICAL 1
2002 WAVERUNNER GP1200R - GP1200A ELECTRICAL 1
2002 WAVERUNNER XLT1200 - XA1200AA ELECTRICAL 1
2003 XLT1200 - XA1200AB ELECTRICAL 1
2004 XLT1200 - XA1200AC ELECTRICAL 1
2005 WaveRunner XLT1200 - XA1200AD ELECTRICAL 1

[ps2fixer]

Yea, regulator requirement would be because their stators are higher output.

Was it only the headlight bulb wired in? What was the wattage of it? The wire diagram says 50w and the taillight is 8w. I don't think a 50w headlight would blow in the system quite that fast if it was the stock stator. How was the regulator wired? The old school 2 wire style basically dynamically adjusts the draw to keep the voltage under a set value and generates heat as a byproduct. Maybe it's blown or has a bad connection.

The part number you listed is for a machine with a battery and looks to be 3 phase, pretty sure that's the wrong part.

This is the style of voltage regulator I'm thinking about where one lead is on the power and the other is on ground.
https://www.ebay.com/itm/1985-Honda-350x-Voltage-Regulator-350-x-OEM-ATC-working/183095301514?hash=item2aa154958a:g:xoMAAOSweWhamKk e&vxp=mtr

The other one linked above has the power run through the regulator, so you have to tap into the power output early, and only connect the rest of the harness to the output to keep it isolated (4 wire design). 5 and more wire is similar but for different alternator designs.

It probably would be best to get a multi meter to test things better.

Since you mentioned you have a 250r regulator, I looked up the wire diagrams for it, and looks like 85-86 were the only ones that had a regulator and is the 2 wire design like the 350x one I linked above. It also states it's an AC Regulator, not 100% sure if it would work with DC, could be part of your problem? Here's a page on how to test the regulator on a 85-86 atc250r. I suspect the voltage test would be done with the meter set to AC. You could test at the headlight plug with the lights turned on with no bulbs hooked up to test the voltage while running. In the service manual they are basically testing the light power wire going to the switches.

It might be worth while testing w\o the regulator hooked up to see what your base line is and see what voltage you get DC vs AC testing.

https://i.gyazo.com/85040af5ff3a311c36ce2a9a070b6ead.png
https://i.gyazo.com/f0a0729bfc2f25f7c7486613af0ed108.png

[ironchop]

Does that part support AC and DC? Like the 350x is AC, the Tecate might be DC, I'm not sure. Based on the wiring, it works with a single field (single phase I guess) alternator, a 3 phase one would require a different regulator, but then again those really only show up when the machine has a stock voltage regulator.I thought I recalled reading on Kawi forum that the Tecate lighting coils were AC so that's why I figure he needed a rectifier with the regulator and suggested that one.

Again, I could be wrong

Sent from my Z958 using Tapatalk

[ps2fixer]

On the rectifier, light bulbs are more or less not effected by AC vs DC if the right voltages are used. The 350x headlight bulbs I use are for road bike application, so they are DC 12v (well up to around 14.6v dc). Batteries on the other hand won't charge off AC, but a simple diode works for them to charge though.

Based on what I've learned lately with the Goki starter kits, the 350x puts out around 14v ac with the regulator working, but when I force the power though a diode, I got about 1/2 the dc voltage than expected on my meter. I guess when DC isn't solid power, meters do weird things like average the voltage out over a small amount of time. I had to run my meter in amp test mode to validate power was going to the battery, which I got 2.5amp draw with it running, so it was working fine. Just some of my experience with the weird world of ac vs dc on these machines. Here's a fun diagram that's a little more deeper into electronics. Basically the AC power when converted to DC though a single diode will only allow the positive power going though, when it reverses the diode stops it. There's also a diode voltage drop that happens on the DC side too ~0.7v if I remember right.

https://www.autodesk.com/products/eagle/blog/wp-content/uploads/2017/04/5176f4bfce395f3a61000000.png

[bryank30]

Ok. I just bought a 80 watt 100 watt headlight bulb. Problem silved? Chime in guys

[ps2fixer]

You have a multimeter right? No point burning up more bulbs, we don't know for sure what output the alternator is, so adding in a regulator would probably be the best idea to cap the max voltage.

[bryank30]

Yes I do. How do I need to configure it to read watts?

[ps2fixer]

Depends if the multimeter can handle it, 100w/12v = 8.3 amps, if the voltage is say 15v, the math works out to 100w/15v = 6.7 amps. Some multimeters can handle 3amp max, 5amp, or sometimes higher. Mine says 10amp max. If you go over the rating, you'll blow a fuse in the multimeter. The alternator keeps putting out more power the higher rpm it goes, so I'd suspect you'd have to get a reading with it red lined to get max output, but there might be a prime rpm it puts out most power. I haven't dove into power generation quite that far to know for sure.

I don't think you can get super useful numbers with a meter like this, but maybe, I've never tried. Generally you're testing how much load is being used, not how much is max possible. Another option is to throw a 10 amp fuse between the head light plug and the 100w head light and if it powers on w\o blowing the fuse, it's atleast close to safe and you could get measurements while the headlight is in use to see how much wattage the light is using.

Anyway, each multimeter is a little different, but mine has 3 lead plugs. Center one is black/grown which isn't moved ever, but the red lead in it's normal test mode spot is for voltage, ohms, and very small amp readings (0.4amp max). To get to the higher amp side of it, I have to unplug the lead and put it in the other hole which is only for high amp testing. The amp test on mine is labeled mA/A for milliamp/amp. Generally the amp test puts the multi meter in line between the power source and the load (generally a bulb in this case). Not too sure if you'd want to short out the power/ground though the multimeter, the alternator might get overly hot from it being a dead short, so in my mind you'd still need some sort of load. I'd guess the 100w light bulb work be high enough to handle idle rpm to get a basic readings and if there's head room to go higher, push it to a higher rpm and watch the numbers. If you go over 9-12amp the bulb will probably blow depending on the voltage.

Now the funny thing, the regulator would be a perfect load since that's exactly what it's designed for. It should have circuitry to limit the max voltage, but I could see it being a simple high wattage resister which might not be a low enough resistance to put enough load on the higher wattage alternator. Getting hard numbers would tell more of the story though.

I know this electronics stuff can get confusing fast, it gets a lot worse when you get into circuit board stuff and current directions in diagrams vs actual true flow etc. You could always just try the 100w bulb and see if it blows, a fuse could protect it from major over powering, but fuses are based on amps, so the voltage would have to be guessed and I think a 10amp fuse is a little high and a 7amp is too low for the 100w load at the variable voltage 12-15v.

[bryank30]

PS2 Fixer. Thank you for the advice. I'll get a inline fuse holder and try that.