thanks guys for your thoughts,i just rounded up all the parts in the list now and im going to assemble the battery and parts,i hope i get the directions right! 
6 Volt LED headlamp w/ small 6 volt motorcycle battery
- Thread starter SgtNorthcutt
- Start date
Diodes have polarity, resistors do not. For the beginning electronics technician, I would recommend leaving out the resistor and zener diode initially. At least until you get your charging system debugged. It will work fine without it for the short term. The white stripe on the rectifier diode hooks up to the battery positive, the other end of the diode hooks to the white wire. Before installing the battery, test by hooking the diode to the white wire and then shorting the other end to the motor case. The motor should continue to run.
Found a good site for the zener diode if anyone is looking for them
West Florida Components: Your Source for Electronic Parts and Supplies
West Florida Components: Your Source for Electronic Parts and Supplies
Well thanks for your help, Scotchmo and crew...
The 6 volt Werker battery is the bomb.
Now I'm gonna give something back to ya's....
Something that I found on ebay and put to use.
How about a Secondary Magneto....? =-]'
Leave the primary alone to charge the spark,
and full bridge rectify the secondary to scoop it all up to dc.
Mini Generator for Motorized Bicycle
I bought one and it works very well.
Once again,
Thanks....
The 6 volt Werker battery is the bomb.
Now I'm gonna give something back to ya's....
Something that I found on ebay and put to use.
How about a Secondary Magneto....? =-]'
Leave the primary alone to charge the spark,
and full bridge rectify the secondary to scoop it all up to dc.
Mini Generator for Motorized Bicycle
I bought one and it works very well.
Once again,
Thanks....
Attachments
BRETT YOU MAVERIC YOU
Youve come accross with the holy grail of bike lighting...this is what we needed all along...I cant wait to get the secondary mag......Perhaps you can post a new thread with all the details...like type of lights your running...wireing....and updates like... "well its still working great".....again I think its great find that hopefully puts an end to the...."can i use the white wire to run my lights?"......J
Youve come accross with the holy grail of bike lighting...this is what we needed all along...I cant wait to get the secondary mag......Perhaps you can post a new thread with all the details...like type of lights your running...wireing....and updates like... "well its still working great".....again I think its great find that hopefully puts an end to the...."can i use the white wire to run my lights?"......J
The Mini Generator looks like a good product for someone that needs a more powerful charging system. If you use your headlight only occasionally, the white wire will suffice to keep your battery charged. If you use your headlight a high percentage of the time or want to run a bigger light without a battery, than this MINI-GEN may be what you need. It looks like the same company also sells a rectifier box called the Mini-Charger. It appears that the MINI-GEN is a single wire unit with a motor ground. The Mini-Charger does not appear to have an isolated negative output, and if so, it must be using a half wave rectifier. For just a few dollars more, they could have provided a two wire output from the MINI-GEN and used a full wave bridge rectifier in the Mini-Charger. That would have effectively doubled the output of the MINI-GEN. You could use your own bridge rectifier but since the MINI-GEN appears to have a negative chassis ground, you will have to run an isolated ground bus to all of your components to use that full wave rectifier. Some components such as bicycle generator style lights may need insulation added under their mounts to isolate them from the chassis ground. Or maybe you could isolate the MINI-GEN by removing its ground connection and running a second isolated output wire to the bridge rectifier. The battery and Mini-Charger that they sell is basically the same system described here with the addition of an indicator LED. You can use their Mini-Charger with the white wire or with their MIN-GEN. I still recommend setting up the most efficient 6V lighting system that you can. Then you can set up the half wave negative ground system described earlier using the white wire and lead acid battery. If that does not provide enough continuous run time for your lights, then you can order the MINI-GEN. And if that still does not give enough continuous run time, modify the MIN-GEN to use a bridge rectifier. As your output increases, it becomes more important to have some sort of regulation besides just the battery. It is not stated if the Mini-Charger provides any regulation. So you may want to use the zener/resistor regulator described earlier in the thread.
I would really like to see them offer an isolated MIN-GEN with two output wire. The user could then decide if they wanted to ground the second wire or not. That would make it somewhat easier to implement a full wave rectifier in the charging system if desired. Even so, I think they are on the right track.
In a word,
I have urethane isolated motor mounts.
The motor is isolated from everything.
My Cree Leds are isolated as well.
So I am full bridge. I run my lights full time
like a motorcycle, day and night. I have a
10 ohm, 1 watt resistor in the system
that steps down voltage to 3.3 for the headlight and
brake light, and then two more that step down the
brake light to a tail light in brightness when the brake
cable operate switch doesn't bypass them. So four
total resistors to eat up some load. Also I have a 7 color
led speedo that was meant for 12v but seems to run fine on 6.
Would you still think I would need zeners so as not to boil the
lead acid battery?
I have urethane isolated motor mounts.
The motor is isolated from everything.
My Cree Leds are isolated as well.
So I am full bridge. I run my lights full time
like a motorcycle, day and night. I have a
10 ohm, 1 watt resistor in the system
that steps down voltage to 3.3 for the headlight and
brake light, and then two more that step down the
brake light to a tail light in brightness when the brake
cable operate switch doesn't bypass them. So four
total resistors to eat up some load. Also I have a 7 color
led speedo that was meant for 12v but seems to run fine on 6.
Would you still think I would need zeners so as not to boil the
lead acid battery?
Attachments
The mini generator sounds good except that it doesn't have any kind of a regulator.
Much over an idle and all my LEDs would go poof.
The Werker 6 volt lead acid battery is big enough to buffer the load I believe.
My Cree Leds cannot have anything over 3.3 volts dc at a 1 watt max.
That's where the resistors come in. I also have a diode on the secondary mag's
red wire, after the full bridge rectifier, set up as a one-way valve, so as not to let the battery discharge back into the mag.
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If your system is well balanced as to output vs load, then you do not need the zener regulator. You said that you run your lights full time. When your average alternator output is slightly more than the draw of the lights the battery will dissipate the excess charge current. The only way to know for sure is to check the voltage on the battery over time. Preferably while the motor is revving. If you never see over 7v, you should be OK. If you ever see 7.5v, you should install the zener regulator. If your voltage readings slowly drops over time, then you will not be able to run your lights full time.
I’m curious as to how you have a blocking diode on the MINI-GEN red wire after the bridge rectifier. Can you diagram it for me? When properly connected, the bridge rectifier will act as a one valve so you do not need to have an additional blocking diode. The additional blocking diode just wastes a little power while accomplishing nothing.
I had to put a diode in after it went dc from the rectifier to the battery
because the rectifier is a small 100volts at 1500ma rectifier. When I first hooked up
the battery I melted the first rectifier because it wasn't strong enough to
hold back the current. The diode solved the problem.
I've got more pressing problems. I went for a ride today and the bike acted funny
and then finally had no spark delivery. This motor and accessories are off of the
Orange Coast Chopper and have been run since February save a couple months in between.
The bobber would come off of idle and then quit. So I would restart it and it would fire right up.
Then next drop in idle it would die when coming to a stop. Fired right up again, so I turned up
the throttle a little. Happened again which tells me it's occurring as a result of higher rpm's for a sustained period a (few minutes). Fired up fine again, but this time when at mid rpm range
and cruising along at 30 mph....dead.
Not able to restart.
My question is can a magneto be intermittent and then die, and also
the same question for the CDI?
The bike ran beautifully all Yesterday. Today was no exception until
the no-spark condition ensued.
I'm puzzled.
because the rectifier is a small 100volts at 1500ma rectifier. When I first hooked up
the battery I melted the first rectifier because it wasn't strong enough to
hold back the current. The diode solved the problem.
I've got more pressing problems. I went for a ride today and the bike acted funny
and then finally had no spark delivery. This motor and accessories are off of the
Orange Coast Chopper and have been run since February save a couple months in between.
The bobber would come off of idle and then quit. So I would restart it and it would fire right up.
Then next drop in idle it would die when coming to a stop. Fired right up again, so I turned up
the throttle a little. Happened again which tells me it's occurring as a result of higher rpm's for a sustained period a (few minutes). Fired up fine again, but this time when at mid rpm range
and cruising along at 30 mph....dead.
Not able to restart.
My question is can a magneto be intermittent and then die, and also
the same question for the CDI?
The bike ran beautifully all Yesterday. Today was no exception until
the no-spark condition ensued.
I'm puzzled.
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That does not make sense. A rectifier does not have to be “strong enough to hold back the current”. It only has to be “strong enough” to pass the current required by your lights without overheating. Even the smallest rectifier can "hold back" a direct short. If your bridge rectifier is hooked up correctly, the blocking diode is doing nothing. If the 1.5A bridge rectifier blew, then you may have hooked it up wrong. Or your lights draw more than 1.5A which is doubtful. If you have a blocking diode hooked up before the bridge rectifier, you are really running a half wave circuit and the bridge may not be doing anything. Without seeing a wiring diagram, I’m just guessing. You should also have a fuse on the battery to protect against excess current.
Pertaining to your spark problems - Electrical problems can be intermittent. Vibration can cause intermittent shorts or open circuits. Heat can cause things to expand at different rates creating intermittent problems. Check for loose connections in all the CDI wires. It could also be internal.
My rectifier wiring is stupid simple, so I don't see how it could be wrong.
Red Wire off secondary magneto to + Rectifier "In"
Black wire from opposite pole "Out" - Rectifier to Engine Ground
Red wire from + DC Pole Rectifier to Battery +
Black wire from - Battery Terminal to Rectifier - DC
Keep in mind the size of this rectifier. It is the size of a shirt button....
What size fuse would be sufficient do you suggest?
Also, what size/type of Zener, and do I put this inline
from the rectifier before battery positive?
I will inspect my wiring today to make sure nothing came loose.
My initial wiring job was for test and fit, so I did not solder nor use heat shrink.
I hope I run into the culprit in my path, so I can go for a ride again.
man, I really love this bike.
Red Wire off secondary magneto to + Rectifier "In"
Black wire from opposite pole "Out" - Rectifier to Engine Ground
Red wire from + DC Pole Rectifier to Battery +
Black wire from - Battery Terminal to Rectifier - DC
Keep in mind the size of this rectifier. It is the size of a shirt button....
What size fuse would be sufficient do you suggest?
Also, what size/type of Zener, and do I put this inline
from the rectifier before battery positive?
I will inspect my wiring today to make sure nothing came loose.
My initial wiring job was for test and fit, so I did not solder nor use heat shrink.
I hope I run into the culprit in my path, so I can go for a ride again.
man, I really love this bike.
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You have two separate coils both producing AC so from what I understand ground on one isn't necessarily ground on the other unless the waves are in sync. Could it be possible that the dynamo coil shorted out the mag coil from sharing a common "ground"? I say "ground" because on an AC system there is no real negative ground, it's whatever side of the wave you use as a common.
The electrical gurus here know a lot more then me but that's what popped into my head first thing.
The electrical gurus here know a lot more then me but that's what popped into my head first thing.
Culprit Found......
- The Mini-Gen Secondary Magneto (sorry to say)
I take it out and the engine fires in a split second.
I put it back in and NO SPARK.
Proposed Reason-
The Mini-Gen comes coated in some kind of black coating other than paint.
It is a very rudimentary piece. I scraped the stuff off of the negative side of
the mini-gen's chassis tang on the top end so it could ground to the same
place as the primary magneto. (it uses two of the screws upper an lower on
the right side to attach itself anyways) The other tang for the bottom (positive side)
I left coated with the black insulated stuff. It appears as vibration and heat has
shown bare metal on the bottom positive tang where the screw goes through.
This I imagine is The Culprit because it is joining inadvertently the 2 poles
of the primary original magneto and messing up the "Field".
Do I get a Gold Star ? =-]'
- The Mini-Gen Secondary Magneto (sorry to say)
I take it out and the engine fires in a split second.
I put it back in and NO SPARK.
Proposed Reason-
The Mini-Gen comes coated in some kind of black coating other than paint.
It is a very rudimentary piece. I scraped the stuff off of the negative side of
the mini-gen's chassis tang on the top end so it could ground to the same
place as the primary magneto. (it uses two of the screws upper an lower on
the right side to attach itself anyways) The other tang for the bottom (positive side)
I left coated with the black insulated stuff. It appears as vibration and heat has
shown bare metal on the bottom positive tang where the screw goes through.
This I imagine is The Culprit because it is joining inadvertently the 2 poles
of the primary original magneto and messing up the "Field".
Do I get a Gold Star ? =-]'
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From your description, it is hooked up wrong. You said earlier that you are using a full bridge rectifier. There should be 4 connections to it. Two of the connections are labeled + and -. They are the output to the battery. The other two might say AC. The two AC input connections should go to the MINI-GEN and ground.
The way that you described would result in a half wave, positive ground system. You could use a single rectifier diode to achieve the same thing. You said that you had another "blocking diode" in the system. Without knowing where your so called “blocking diode” is connected, it is hard to tell what is actually happening. As it is you have an incorrectly wired bridge rectifier and one redundant component. The end result is something that may work, but is inefficient and needlessly complicated.
I use a 5w 6.8v zener for my white wire system. When used in conjunction with the 10ohm power resistor, it should still be big enough for your MINI-GEN regulation. The series string of zener and resistor go across the battery + and – to bleed off current when the voltage exceeds a certain limit. Look at the diagram I posted earlier in this thread. Don't worry about the regulation until you get your rectification circuit straightened out.
I use a 10a fuse but that it up to you. I usually size it so as to protect the wiring or maybe twice as big as your total current draw.
That is exactly how I have it wired...
4 connections (diamond pattern)
Top - + Mini Gen
Bottom - Engine Ground
Left - + Battery
Right - Negative Battery and Engine Ground
This is wired per the schematic on the back of the package from Radio Shack.
The only marking on the rectifier is a "+" on one of the poles. I imagined this to be the AC "in".
4 connections (diamond pattern)
Top - + Mini Gen
Bottom - Engine Ground
Left - + Battery
Right - Negative Battery and Engine Ground
This is wired per the schematic on the back of the package from Radio Shack.
The only marking on the rectifier is a "+" on one of the poles. I imagined this to be the AC "in".
Hey Brett, is there any way to get a close up shot of your Mini-Gen? The pics they have of it on ebay are kind of crappy (everything else they sell has nice close up shots) and I have to wonder if there's a reason. Maybe it's because if someone gets a good close look it wouldn't be hard to replicate one? lol