Mdl 95 trail lighting ????

[dcooke007]

Currently working on a Combat Wombat that is going to be used for woods / cross country racing. Trying to shorten the learning curve with your help and not have to do go through all the experimentation that you guys have already experienced. Bike will be equipped with Strictly Hodaka's 6 volt Preston Petty front number plate / light and matching rear fender with stop lamp.

I could use either model 94 or 03 wombat lighting coils as I have access to both. Studied the wiring diagrams and noticed the head lamp and tail lamp is powered by ac voltage with a current limiter or voltage regulator depending on 94 or 03 model. Also noted the brake lights, horn and turn signals are dc powered with a rectifier used in both the 03 or 94 model.

With that info in mind can I just use only one lighting coil? Ac voltage with voltage regulator or dc voltage with rectifier?

Thanks,
Danny Cooke

[Dale]

Danny,
I think the answer is simply to go 100% AC with the regulator. The DC option would call for a battery too.

I have not compared the lighting coils between the 94 and 03 models. The 03 could have a higher output, but not sure that you would need it anyways.

(Roger... are you out there???)
Dale

[BrianZ]

I had a look at the 94 wombat wiring diagram and I'll offer up my advice, for what it's worth.

Let's forget about the ignition system, as you already have that working. So removing the ignition from the equation, there are two output coils in the magneto.

When the lights are off (key switch set to day), one of the output coils is switched to the rectifier. The only thing this coil is doing is running the brake light and charging the battery via the rectifier. The battery then supplies the horn, so very little load.

When the lights are on (key switch set to night), the two magneto output coils are connected in series. This provides more power for running the extra load imposed by the headlight, tail light and speedo lights.

Since you are planning on running a headlight and taillight, I would use both coils connected in series. Assuming you are not using a battery, get rid of the rectifier. To protect the lights from over voltage, I would also connect an AC voltage regulator in the circuit, like the one used on the Road Toad.

Brian

[rlkarren]

Danny,

Did you want to go "always on" or 100% AC? I think both are possible.

but.. I'll copy from an earlier post... "If you use only one lighting coil, the max output in Watts is about 20W". Both coils are generating AC current at ~20W each for about 40W total output because they are wired in series already.

To make a long story short, the yellow wire from the magneto is the wire carrying 40W of AC power. The key switch simply switches AC power from one coil that is converted to DC current to two coils that generate AC current, some of which is routed through a rectifier to convert it to DC current.

It's late, but if I get some time tomorrow, I'll look at the diagrams and see what can be done to go 100% AC. I think it would be fairly simple.

Roger

[dcooke007]

Roger,

Would probably wire a switch to turn headlamp off / on and brake light working all the time. Single element 6 volt headlamp and brake lamp. Not that complicated really but if you guys have already gone through the learning curve it would save me some time. I can go either dc with rectifier for both lamps or ac with voltage regulator. With out experimenting I am not sure whether ac or dc works better with regards to bulb longevity, headlamp out put or lamps dimming at low rpm with out a battery. The 03 wombat lighting coil arrangement is rated at 45 watts....of course assuming this is with both lighting coils. I was thinking I might be able to only use one lighting coil but looking at the headlamp rated at 35 watts raises questions. Looks like I might have to go with both but was hoping to save some parasitic drag on the engine by using one lighting coil. The engine for this project is currently being rebuilt so it will be a few days before it is ready to test any lighting arrangement. Any additional info is appreciated.

Thanks for every ones input so far.

Danny Cooke

[viclioce]

OK so I'm joining in on this thread as we have similar issues.

First question is this. With a Model 94 bottom end, and only one coil on the stator, how do I determine the wattage output of the single stator? 20w? 25w? Need to know how to confirm.

Second question is where can I get a second coil and then how would I wire it in? I saw earlier in the thread they should be wired in series. How is this accomplished? Do I have to replace the stator plate or is there a way to attach a second coil to my existing stator? Photos can be uploaded if needed

My headlight is a dual filament 6v 35/25w sealed beam unit. Not original to this bike, it was an eBay purchase. I would be willing to trade it to someone for a single filament if there is someone who wants to make the trade, as long as it fits my bucket & yours! ; D Victor

[dcooke007]

Found the instructions on Strickly Hodaka web sight for the Combat Wombat lighting kit. Looks like it only used one lighting coil and since there is no rectifier in the kit it is running on ac voltage. The only lights used on this kit are the headlamp and tail lamp.

Also noted no voltage regulator was used and a warning was mentioned that this was a "direct" system and voltages varied widely based on engine rpm. Stated also that filament life is related to engine rpm. Link to article http://www.strictlyhodaka.com/v/vspfile ... OMLIGT.pdf

So looks like one lighting coil "may" be sufficient with ac voltage for the headlamp and tail lamp and adding the voltage regulator "should" address filament life. All this assuming the lighting coil used in the kit were the same as those used on production Hodaka's with the same wattage out put.

Victor, not sure what the individual lighting coil out put is at this time as the service manual listing is not that detailed. The lighting coils should be available from Strictly Hodaka and you should be able to just add it to your stator plate and wire accordingly. I should have a stator around here some where and should be able to post a photo. I would suggest the model 94 lighting coil as that is the engine you are using....a or b depending on which one is missing. Not sure at this moment if the 94 and 03 lighting coils are inter changeable. The 94 model was wired so the headlamp could be turned on or off but the 03 model was wired for the headlamp to be on all the time with the engine running. When addressing your re-wiring issue you should consider this assuming you have a working 03 ignition switch and related lighting switches.

Danny

[rlkarren]

Danny,

That was a good article that did all the work for me. The only thing that causes me to wonder is the output rating of the coil that is included in the Trail lighting kit. If it's the same coil as Wombat's, it would have an output rating of about 20W, which would dictate that the headlight is a 15W model, leaving ~5W for the tail/stop light.

As a note, the Hodaka light coils are already wired in series so if you wanted to use two of them to run a higher wattage bulb, simply run the output of coil A to input of coil B. Then, the output of coil B is your 40W of power. (Assuming Coil A is on the right and coil B is on the left as you look at it).

If I read the article correctly, I would definitely place a voltage regulator on the brown wire coming from the light coil. Theoretically, you can place the VR anywhere in the circuit, but I prefer to place it inline before any lights. Where it says to run the "brown lead from the coil to the headlight body", I might run the brown lead under the seat, splice in a VR with a double connector, make sure the VR is grounded, then run it to the headlight body.

$0.02

Roger

[viclioce]

Danny. No ignition switch, no secondary wiring harness of any kind. No battery, no battery box. I do have the combination hi/low switch & horn button. I believe the PO was possibly using the horn button as a kill switch?

I am still working on getting this beast back together. My kickstarter lever failed and I am awaiting a replacement in the mail. I put oil in the bike today, and the clutch cover gasket is leaking in 2 places on the bottom so I have to drain the oil again and check the casket for placement. Hoping it's not damaged.

Lots to do. Want to ride her some day! I've had her for almost a year now and have only heard her run once & she had a cracked top piston ring at the time! Perseverance is my new motto! ; D Victor

[viclioce]

I see the model 94 lighting coil on the parts list, available for $21.95. However, the wiring harness piece which connects the coil to the wiring leads for the lights is not available. Is there a way to attach bulk wire to the coil? If so, I could be on my way to lights with just the coil & screws needed. If not, I may have to find one somewhere. : D Victor

[dcooke007]

Victor, you MAY not need the other lighting coil. At this point my project is on hold waiting for parts so it is going to be a week or so before I can test my assumptions. I think I can point you in the right direction though.

So at this point you should have one exciting coil that powers the ignition and one lighting coil with output wire going to ????

1. The lighting coil you have should be grounded on one end and have an output wire coming from the other end. What color is the wire coming from the lighting coil? Does the wire go up the engine harness to the white connector that connects to the main wiring harness?

2. Is the bike still equipped with the voltage regulator? This a link to the parts illustration and I think it is located under the fuel tank. http://www.strictlyhodaka.com/SearchRes ... p?Cat=2215 If the main wiring harness is still intact we should be able to connect to it with out having to totally rewire.

3. You need to have working circuits for the headlamp, tail lamp / brake lamp, voltage regulator and you mentioned the horn also. A working kill switch is also required. If you want high and low beams that needs to be planned for also. My thinking is if the main harness is still intact you can connect to it.

4. Once the circuits are established you can connect the single lighting coil and test your results. If two lighting coils are required the only change that would be required would be to add the second coil.

Let me know what you have.... voltage regulator, main wiring harness intact, brake lamp switch / switches and lighting coil wire info.

Danny

[viclioce]

Nope. All I have is the exciter coil for the generation of spark for the ignition. Three wires come out from that. Blue, black & yellow. Yes I have a regulator under the tank right behind the spark coil. Pieces here and there after that. A couple of wires running up to the steering head, a brown & a green, assumed to be primary power lines for the head/turn signal lights. Also two wires were left running to the tail light. I believe a brown & green also. There was no rear brake switch so I acquired one from another motorcycle and wired the tail light into it. I think I may have it wired to what's left of the main harness through the brake switch to give power to both file T's when the rear brake is applied, but I can't test it until I get my replacement kickstart lever so I can start the motor again. There is so little harness left that the only way to demonstrate what's left will be to take some photos and post them. But, I don't think I currently have enough wattage output to both run the ignition and power anything more than the tail light bulb with only the exciter coil. I have both model 03 wIting diagram and a model 94/94a diagram, but with so little wIting left, it's difficul to determine power path possibilities. Ultimately, I can choose from the blue or yellow wires, and I assume the black is the ground return for the exciter coil? More to come, with pix! ; D Victor

[Bullfrog]

Victor:

The stock ignition exciter coil mounted on the stator plate normally only has a bare brass colored eyelet attached to the "ground end" of the coil. The eyelet is "captured" under the head of one of the coil mounting screws. The other "end" of the coil winding wire normally has green insulation - and this wire terminates in the solder joint at the top of the condenser. Notably (and importantly), there are NO OTHER WIRES coming off the ignition exciter coil. So I'm wondering whether your magneto even has the proper coil for ignition.

Here is how you can differentiate between the ignition exciter coil (which is the same on the Wombat AND the Combat Wombat) and the lighting coils on the Wombat. Check the resistance of the coil windings on the coil - the ignition exciter coil should exhibit 2.0 to 2.5 ohms resistance. The lighting coils have fewer windings of heavier gauge wire so they should exhibit only about 0.2 ohms of resistance (each).

I'll be interested to hear what you find.

Ed
PS: Danny, I could hardly believe it but . . . I connected to the green (battery charging circuit) wire of the Wombat lighting system and went simple AC power with a 12V aftermarket voltage regulator. With a 12V, 100 watt head light I could almost make Ponderosa Pine bark smoke at 30 paces with the light output! I've since switched to a lower wattage bulb to reduce the heat output to protect my Preston Petty Headlight Number Plate unit. (the solid state 12 volt regulator "dumps" extra voltage so the lower output bulb is protected from being "over powered"). I only run the headlight and a taillight - no other electrical items on the machine.

[dcooke007]

Hey Ed, thanks for the info... that was what I was looking for and should save me a little time. An interesting thing to note is the 03 Wombat uses the green stator wire to power the headlamp and tail lamp. The yellow stator wire powers the d/c circuit. Also the headlamp is not switched and is always on. The bike I am working on at the moment will have one of Paul's six volt headlamp / number plate and tail lamp. I am still contemplating using just one of the lighting coils. Since those parts have already been purchased I am planning to use the 03 model six volt regulator. It would have been interesting to try 12 volt but this bike is on a time line for racing this spring as well as budget. I am rebuilding and refinishing the engine with reed valve and modest porting.

Danny

[dcooke007]

Hey Victor, below is a picture of a very worn mdl 94 stator assembly. Some of the red fiber type insulators at the ends of the wire coils are missing and any coil in this condition should be considered unusable. The exciting coil is at the top to the left of the points. It is easily distinguished from the lighting coils as the exciting coil wire is smaller gage and is fairly even across the top of the coil windings. Both lighting coils have larger gage wire windings and you can see the step across the top of the coil windings.

Here the two lighting coils are unfastened to show wiring detail. The yellow wire with green strip is not used for any purpose. It is simply folded back and taped over in the harness.

This is a 95 model stator assembly and this comes set up for ignition only....no lighting provision. This is the unit I will be rebuilding and adding a lighting coil...may be two lighting coils.
Danny

[dcooke007]

Victor, I failed to notice your concern about the new lighting coil not coming with the associated wiring. Yes you would just solder the appropriate gage wire to the lighting coil and insulate the solder joint with heat shrink tubing. I like to use the adhesive lined type as it seals out moisture and other contaminates. There is a coating on the lighting coil wire so you would have to remove the coating at that place to solder the connections. Care should be exercised not to remove the insulation coating from any other part of the coil winding wire.

Danny

[Zyx]

Some of the red fiber type insulators at the ends of the wire coils are missing and any coil in this condition should be considered unusable.

I am curious why you conclude that the absence of some of the original fiber insulator material makes the assembly unusable. The insulation is essentially static, and was primarily used as a winding guide when winding the coils. Once constructed, the value of the fiber boards goes away, if these coils still check out electrically, they are very useable, and if you are concerned about vibration dislodging the windings, or some other degradation that might arise from missing fiber boards, you can stabilize the area where the boards were with Right Stuff or Shoe Goo, clean the coils with alcohol, and top coat them with clear coat. The reddish coating on the copper is usually a form of lacquer-based varnish similar to Indian Head sealant. You can recoat with either clear lacquer or clear urethane. It doesn't take much.

If the coils do not check out electrically due to short, that can be fixed as well either by locating the short, or if it is hidden, by rewinding the coil. Either way, tossing them out isn't the only answer. I recently replaced my stator assembly on my RD350B with a unit that was so trashed by corrosion and dirt I thought it had to be a flood recovery piece of junk. But I found it was electrically sound, so I cleaned it carefully, recoated it, and put it in service. It now looks new, whereas another assembly I bought at the same time which looked perfect was DOA due to electrical short, just like the original stator in my bike. I opted to recover the ugly duckling that was electrically correct, and save the other for future parts.

These coils either work or they don't. If they do, they can be used again. If they don't they can often be recovered if you are patient. Even if you have to rewind them, it isn't rocket science.

[Zyx]

PS: Danny, I could hardly believe it but . . . I connected to the green (battery charging circuit) wire of the Wombat lighting system and went simple AC power with a 12V aftermarket voltage regulator. With a 12V, 100 watt head light I could almost make Ponderosa Pine bark smoke at 30 paces with the light output.

Electrical output, AC or DC, is simple math: W = V x A. This never changes. If you were able to fire a 100W filament as described, you could only do so by increasing the voltage output, or by increasing the wattage output as a function of rising voltage. Since the wattage is roughly a targeted result of the number of winds and gauge of wire in the coil used in an environment with a limited range of rpm, the only real variable is voltage, which when it rises takes wattage along with it. As engineered, it is supposed to produce target wattage early in the rpm range, somewhere just off idle.

The magneto will produce a variable amount of voltage dependent on rpm. Given a fixed rpm adequate to run lights, if you could fire a 100W bulb without hitting 10,000rpm, then I would have to say your voltage regulator is not working. Limited to 12 volts more or less at some optimal rpm, your wattage output is also limited after the voltage limit is reached. Because your lighting coil is only intended to fire small wattage bulbs, 20W or so, in a properly limited circuit, a 100W bulb would glow yellow but that would be all. Since it turned into a flame thrower, something is not right. I would also guess that you have no fuse in the circuit or you would have popped the fuse.

If you run a smaller bulb on an unregulated circuit, it won't last long. I would check the voltage output over your rpm range, and verify there is a working limiter.

[BrianZ]

A coil may be capable of an output higher than its stated wattage. Engineering specifications are often conservative for the sake of reliability. Typically the limiting factor is heat. If a coil is operated beyond its specifications it will generate more internal heat. If the heat exceeds the rating of any of the materials (usually insulation) it will fail, but this does not mean it can't generate more than the stated wattage for short periods of time.

Brian

[Zyx]

I already said that. As voltage rises, so does wattage. It isn't a matter of being conservative in engineering as being conservative in cash outlay. Starting with the then accepted need for trail lighting in terms of readily available DC lamps, a certain amount of output is needed to support both the lamps and the battery, and the battery took up a lot of the slack in electrical demand. That's why it was there.

My point is that there is no way to have fully fired a 100W bulb with a 20W circuit without raising the bar somewhere. Since the coil was presumably not rewound, and limited to the rpm range of your average Hodaka, voltage HAD to have been way above 12. Run the equation in reverse. Start with a 100W draw, and you have to have something on the order of 33 volts at three amps, or 20v at 5A, or some other combination of voltage and amperage that would produce enough juice to fire a 100W load. Amperage tends to cause wiring to get warm if it is higher than what the wire is rated to handle. Hodaka wiring is something around 18 to 22 gauge, and will only handle amp loads higher than 10A for short periods. To result in 100W, the circuit had to be providing not less than 8.33A at 12 V. Assuming the limiter was working and holding voltage to 12V, the amperage available from a coil intended to provide more like 2 or 3A would be far less than 8.33 without causing heat damage in short order. So I am assuming that the voltage was free to rise well above 12V and was also providing the related amperage sufficient to result in a 100W load. Without having the bike in front of me for testing, I can't say what two of the three variables were in a watts equals volts times amps circuit. But whatever it was, it was way beyond what the coil and circuit was built to handle. Hence, my warning about checking the voltage limiter, since that is the only limiting device in circuit if there was no 3A fuse as there should be. The fuse limits amp rise, the volt limiter limits volt rise. Something is either missing from the circuit, or not working. Otherwise it could not cause a 100W lamp to put out a hot light.

[dcooke007]

GMC,

I have noted Hodaka stator coils shorted when the red fiber coil end insulators are missing. The red insulator does serve an additional purpose other than a "winding guide". The coil windings on both of these coil assemblies are loose on the metal cores and have shorted out. This is due to the missing insulators, resulting lack of support and vibration causing the winding to rub the core.... as you mentioned. I have unwound a few of these coils to save the core and there is an insulating material between the core and the windings. When operated with out the red insulators the insulating material is rubbed through /away by the vibrating windings.

Your thoughts on using Right Stuff / rtv automotive sealant to replace the damaged or loose red insulators would certainly work if the condition was noted before any damage occurs due to vibration, looseness and resulting short circuit.

Rewinding the coil is a viable option and the insulating material between the core and the winding would need replacement if not in good condition. Most Hodaka stator coils are available and not to costly at this point. As long as that is the case replacement seems a better option. I do strip the copper windings for scrap and save the metal core if the supply situation changes in the future.

Danny

[Zyx]

I would always go with the cost-prudent choice also. But even if shorted or open, it is the core that hides the technology we can't fake. Copper wire is easy to find. Lots of choices out there for magnet wire in a wide variety of gauges. Insulating wrap is easy to fake as well. But the material and design that go the coil core is not something the average guy can whip up in his basement, so I would not throw away a stator assembly, even if it was deemed no good anymore. Rewinding isn't that hard, and with practice, one might even be able to get a bit more juice out of a rewound coil than was there to start with. It would be something that I would find interesting to try, to bump up the output of a lighting coil.

[dcooke007]

I have been researching the lighting system on the mdl 94/94a Wombat.
Listed below is some info from the Wombat workshop manual.

With the main switch in the DAY position......
1. current is supplied through the battery to the stop lamp, turn signals, horn, speedometer light and are of course DC powered.
2. the GREEN wire from the stator in conjunction with the selenium rectifier is the source of DC current to recharge the battery. If there is no battery the GREEN stator wire would be the sole source of electrical power to the components listed.

With the main switch in the NIGHT position.....
1. current is supplied through the battery to the stop lamp, turn signals, horn, speedometer light and are of course DC powered. If there is no battery the YELLOW stator wire would be the sole source of electrical power to the components listed.
2. the YELLOW wire from the stator in conjunction with the selenium rectifier is the source of DC current to recharge the battery.
3. the same YELLOW wire from the stator provides AC current to the headlamp and tail lamp.

My conclusions are...
1. both lighting coils are generating current any time the engine is running. Whether any electrical load is applied to either or both lighting coils is determined by which circuit is completed....green or yellow stator out put wire.
2. the green stator out put wire only supplies current from lighting coil b.
3. the yellow stator out put wire supplies current from both lighting coils....a & b. Lighting coils are wired in series.
4. the highest out put should be from the yellow stator out put wire. I came to this conclusion because all electrical current is supplied through this circuit only when the highest electrical load is applied.

I arrived at these conclusions after studying the wiring diagram, system description and unwinding the a and b lighting coils. I am not an electrical engineer but I think this is correct.

I know this is not a direct answer concerning the 12 volt conversion but understanding how the system operates may prove useful. In this case I wonder if the yellow stator output wire may hold some potential. It would also depend upon the amount of current required for the load applied to the circuit. If one lighting coil is sufficient for the load then perhaps parasitic engine load can be reduced? If dc voltage proves more reliable for bulb longevity but requires more current would the yellow stator out put wire supply the needed current in conjunction with a rectifier? Just some things to ponder at the moment.

Danny
dcoooke007 Posts: 82Joined: Fri Aug 23, 2013 8:11 pm

[Bullfrog]

Danny,

Like you, I am not an electrical engineer, but I came to exactly the same conclusions you did. (That's a good sign right? )

But here are two additional comments:

1. I selected the green/yellow-with-green-stripe wire for my "source" precisely because I expected it to be "low output" - and found that I could make bark smoke at thirty paces with the 100 watt 12V headlight. I also joked about pumping so much energy out the front that my top speed on the highway dropped! I have not tested using the "high output" yellow wire - there seemed to be no need since I already had more "power" than I really needed .
2. The power rating of the coils as listed in the manual is inextricably linked to the electrical "load" the coils are actually connected to. Change the "load" . . . and the ratings change.

Ed

Ed

[dcooke007]

Ed,

Well they say, "great minds think alike". Hanging out here just does something to a feller....good things.

Danny