Lighting Coil 93 Super Rat

[River Rat]

I have a 71 Super Rat that had a headlight and tail light on it when I bought it a few years ago. I just got around to working on the lighting and determined that the lighting coil must be bad, no short but 0 resistance. The coil has two wires coming from it, one small green and one larger yellow.
I would like to have the lighting system on the bike so I am wondering what lighting coil will work and what the output wattage would be. I have checked the threads and believe a 100 B lighting coil will work but I need some guidance. Can anyone steer me in the right direction?

Thanks!
Dan

[efkruger]

I want to put a light on one of my 93's that I ride around the place on so I hope someone can help with this also. Having that light comes in handy.

[Bullfrog]

Dan,
I believe you are already headed in the right direction - the 100B lighting coil should be a "bolt in".

Ed

[Hydraulic Jack]

Output from a 100B system is nominally 45 watts at around 8 volts. Light output isn't modern by any definition. I think of the old Hodaka lights as about on par with a Boy Scout flashlight.

[viclioce]

I would love to find a headlamp unit that holds h4 lamps to fit our buckets. I could then mount an LED lamp and those suckers are BRIGHT.

I recently put a Cyclops 3800 in my VL1500 and they now make a Cyclops 7000! Blue/white light, extremely bright and very little wattage! Victor

[Bill2001]

One lighting solution I looking at involves a 6000 Lumen head-mounted lamp that is focussable from a broad beam to a tight spot. That focus feature can be used in the same way as a high-beam, low-beam for off-road work. It is designed to operate on four AA cells, which is 6volt, low amperage operation. Running it from the battery bus, which would constrain the voltage to 6 to 8 volts it should work well. It can be mounted as an auxiliary light next to the headlamp or mounted on the handlebars.

[River Rat]

Thanks for the response, I'll go with the 100B lighting coil and the appropriate headlight. I will add a voltage regulator. Looks like the Road Toad/Wambat voltage regulator will work unless there is a less expensive 2 wire unit out there?

Dan

[MTrat]

Bill2001, Looks like a great topic for a Resonator feature. Very interesting...

[River Rat]

Ok, before I trash my coil, I checked resistance again on the ohm meter, set at 200 and I have a resistance in the coil of .5. I think this is an indication that the coil is bad. I don't have a manual so can anyone tell me what the resistance should be for a lighting coil? Sorry about the manual, I'm working on that too.

Dan

[rlkarren]

I did quite a bit of research on the headlights and electrical systems for these Hodakas a couple years ago. If you look at some of my previous posts you'll find just about everything you need to know about the headlights, electrical system, and appropriate replacement optiins.

Some of these options included an H4 6V 35/35w and another option for a 6V 15/15 w bulb, both are halogen. Both options have vintage lens's.

The Ace light coil actually only puts out about 18 W total. For a Super Rat light kit you would want the 6 V 15/15 W headlight that I mentioned in earlier posts. Even though the light coil will still drive a 12 V bulb, the output brightness would suffer because it's not running at full power, which in turn would cause the light to fail prematurely.

$0.02

Roger

[River Rat]

Roger,

Thank you and I did read your posts and that's where I was headed. I'm still curious about the resistance in the lighting coil. I will check you posts again to see if its there somewhere.

Thanks again,
Dan

[Bill2001]

Don't know about an SR-93, but on the WBat-94 with two lighting coils the combined resistance is 0.5 ohms, yellow wire to black ground wire.

[River Rat]

I'm getting .05 with no short but I have no voltage. Interesting?

Dan

[River Rat]

I'm wondering if the SR flywheel is insufficient to power the lighting coil? The 100B and SR show different part numbers for the flywheel.

Dan

[Al Harpster]

Factory spec for 18 watt coil is stated as point four ohms. Found this on page 26C Hodaka workshop manual supplement for model ace 100B.
I don't have any information about flywheel part numbers, perhaps someone else does.

[Bullfrog]

Um, let's not over-think this. Put on the lighting coil and go. Flywheel variations MIGHT mean you could use a 16W/16W headlight (and those are EXTREMELY rare ).
Ed

[River Rat]

Ed,
Ordered a new lighting coil and will hopefully report back with voltage numbers next week. I'm going with the fact that a prior owner mounted the appropriate headlight and coil and they must have worked at one point because they stayed on the bike. So what could have changed by the time I bought it? Only the lighting coil. I appreciate the input and you are right, keep it simple!

If this works here is my flywheel, 4 magnets.

[Al Harpster]

But Wait! There's more:

The B+ lighting coil has two taps with two different ratings.

Maybe this will help...

[River Rat]

Ok Kids call me nuts but I have to know why something doesn't work. I unwound the coil that did not work, about 30' of wire. I found spots where it looked as though it had gotten hot and melted the coating. I pulled it tight, shop door to the Model A pickup. Hit with a coat of high temp spray paint, yes I know. Let it dry and rewound the coil, not fun and it came out prety ugly, oh well it was just a test. Still had .5 ohms resistance but amazingly I have voltage and the lights work! The voltage jumps around based on rpm but is within the perimeters and the bulbs are bright. You can come to your own conclusions.
Thanks for all the help, information and suggestions!
Dan

[matt glascock]

Coil to core fault. Cool repair. I never thought of doing that. I wonder if there is a legit lacquer designed for just that purpose. Some of these coils are getting impossible to find so a reliable repair scheme would be great. What a great Resonator Revisited article that would make.

[Hydraulic Jack]

I wonder if there is a legit lacquer designed for just that purpose. Some of these coils are getting impossible to find so a reliable repair scheme would be great. What a great Resonator Revisited article that would make.

Yes, of course there is, as well as sources for new, lacquered wire to do a rewind. Google it. There are still shops that rewind motors and related coils so the supplies are still out there.

[matt glascock]

That's great, Jack. Thank you. On that same theme, I have sizeable stash of blanks. Are these the same as the cores for the corresponding coils and could they be wound appropriately for replacements some day?

[Hydraulic Jack]

Matt,

I have no reason to think they are different in any way from the cores used for winding lighting or ignition coils. Try one and see. It could be either entertaining, educational, or very frustrating, depending on how you view winding wire around a core. Will need some winding shields, but their principal function is to keep wires from wandering, not insulation per se, so heavy card stock soaked in a good paint might work. Not sure where you could find the actual material used for the reddish paper winding guides. I have always thought that winding your own coil would allow you to up the wattage output.

[matt glascock]

I'm a glutton for punishment so winding wire around a coil might just be up my alley. I have a huge pile of blank cores that came with a parts stash that are doing absolutely nothing. Sounds like a match made in heaven. That red material looks similar to the fiber washer material used on petcocks, oil plugs, etc. I'll dissect a roached out coil to copy the length, wire gauge, and construct. What the hell.