Schwinn Point Beach FD Remake

CB2... Very nice indeed!

With the gen rub on the rear tire side for front head lamp, does it have a battery for when at a stop and engine idle?

I would think it is already been mfr'ed or atleast someone has done it here. As an electronic tech I off hand right away would think a rechargable battery and and circuit regulated meant to charge the battery from the gen. The light tapping energy from the battery while at stop.

The other way hook another gen meant for a range of engine speed right at the crankshaft, but please keep a fake tire rub gen for looks!

The retro stuff but shining is just as good as the unpainted rusty!

Measure Twice

CB, I have just looked over your reply. Please note right now after me being a light weight and having just found I can get Shlitz Beer with the retro Classic 1960's Formula, I can just reply in overview.

The diode would be in series between the generator and the battery so that when you’re at a stop and there is no current from the generator flowing, the battery does not charge the generator. Funny I said that, but I suspect you know that a generator would not like to get a charge.

A few more things are that the diode will probably have a forward voltage that will drop about 0.6 volts so that the generator has to put out enough to overcome both the 0.6 volts plus about 1 volt above the battery to allow for charging. If it were a 6 volt battery and 6 volt generator that would not do, it would have to be 6 + 0.6 + 1 = 7.6 volts output from the generator or higher.

Thinking of what could work is I’m remembering that they were 6 volt generators, so that two just using three of the high amperage hour AA rechargeable nickel metal hydride cells (like the Enercell 2500 mA) in series for nominal 1.2 times 3 = 3.6 volts could work in a scenario.

The diode also must have enough current capability for the job or it will burn out. This is where a current limiting resistor can be added also in series with diode so that just allows for a trickle charge of the battery and the diode is saved as well from over current as it does get the same current through it.

I’d have to look at the specs of the parts first before getting any of the parts to know it would all work out. I just thought that Nuts & Volts Magazine I have subscribed to or ARRL probably have a circuit worked out. I’ll check on that. But since I was going here is the rest in a pinch.

6 volts minus at most 1.25 top off volts times 3 = [6-(1.25*3)] = 6-3.75 = 2.25 volts 2.25 volts > 1.6 volts by 0.65 volts to spare.

With particulars not yet figured but can be done later for the components for the trickle charge circuit to the battery, using a handful of the real bright white leds would mean most likely the generator charging the battery would be enough never to have to take the batteries out and charge them with a home charger.

Though the huge bulbs if you could get them in a lower voltage so that they could work with the 6 volt tire rub gen in the above scenario would be fun to see operating full retro. Those dotted bulb surfaces for the light diffraction are such a charm, unlike the leds.

There is actually a way to overcome the problem if you really want the retro bulbs and the 6 volt gen and 6 volt or whatever came with the gen light set uses for bulb voltage that are too high to work.

This is a very small DC to DC converter that is about 15 or 20 dollars and is adjustable. If I remember right it took as small as like 3 volts and had a step up to as much as 20 volts with a little loss in current, but still efficient. It was rated at about 1 amp. No one could be the wiser why you had light output while idling!

Measure Twice
PS …. I’ll look to see what is already been done and get back to you

A slow charge when at speed made possible by limiting the current with a resistor is what is called a trickle charger. Having a greater voltage by a small amount is at least necessary to have the battery get charged. If the voltage is a lot more to a point, it really still does not matter as long as the current is limited by this part called a resistor. The ohm value of the resistor is chosen to limit the amount of current that flows.

Now what you said about having them separate altogether and no charging from the generator to the battery, that is a different story. I think it is a good way also.

I did a similar thing a while back with a getto blaster so that when in my car without a FM radio or cassette player installed in my car, I could use the car battery to run my getto blaster and turn off the connection to the internal D cells so as to save money on batteries.

I used a relay and when I plugged a cable to the cig lighter and to my getto blaster I had the D cells inside the getto blaster disconnected and the car battery supplying the getto blaster instead.

This was done by my connecting and disconnecting, not what you want done manually.

It can be automated and a special diode called a zener diode and a resistor. The zener diode is specifically different than a regular diode allows you to pick a voltage that you want to drop from a circuit. So where it all comes together is choosing a relay that will activate its coils and trip the relay to switch when the generator output is enough to give a respectable amount of current to run the head light and save the battery pack, like at 9 volts. There is just one thing additional that if the voltage on the generator does not go up to near the 12 volts as you said it does at slow speeds, but rather ramps up, you could possibly be going at a speed that the relay starts to try to close, but instead chatters.

Additional circuitry to eliminate that with an op amps configured as comparator with a degree of hysteresis (no middle) could be added. The op amp could use power from the battery to operate and the amount it uses is next to nothing.

I’ll look to be see what has been done on that kinda circuit. The library and many online educational places have a lot for free on this. One that always comes to mind is HowStuffWorks.com Take a look there, lots of stuff!

Measure Twice

Hey CB, your new build is awesome! I like the design, simplicity and easy adjustment of your drive train too.
The 24" wheels and nice fat tires are perfect . Just right proportionaly, for that motorbike look and feel.


If you can change to 12 volt system, all you need is a mower or snowmobile regulator. I have experimented with them when I was building wind powered experimental aircraft generators. Works fine with smallish seald batteries(5ah is what I've used for years, smaller would prolly work.) They work universaly with ac input from lighting coils, or perm mag fan motors ect. Even tried a kiddecar motor with good results.

P.S. I realy like your clutch cover. What did you make that from. An air cleaner?

It's definitly got style, and coolness! If your set-up works anything like mine, you ain't gonna want to ride the Mongoose so much .
It's gonna be your "everyday rider" cuz you gonna like the way it runs so much you won't want to use the others LOL. This type drive and engine set-up is very quiet, reliable,easy to operate and maintenance free. Feels and operates as good as anything factory made.

You realy built an awesome machine with lots of character.

Ben

aw-sum!! Looks as good as a whizzer !! The engines with the angled cyclinder`s fit so nice in frame`s when used in reverse rotation drives. They also look better in that position.

May have to go that route in my stretch cruiser. By the way, was expecting you to pop up with a new build!! Lol you just can`t help it!!

Thanks for sharing . I have extra 49cc sticker`s if you have need !! Ha ha

Ron ..

I found on a preview only from Nuts & Volts as currently a non-member a Q&A area of a search on "Bicycle Generator" and since it was not a long article being in the Q&A area anyone as non-member can view all of it.

The Answer to #3083 March 2008, How can a functional, small generator with voltage regulation be built to operate on a bicycle........

Nuts and Volts - May 2008 generator&doc_id=-1#pg111


I found this, but know that the generator for bikes are usually AC alternators and although called generators would need to be rectified to DC to charge a battery.

Not all the fine details of building it are show in the answer, but a less sophisticated way of having it switch from generator to battery automated was mentioned. It was accomplished by using a length of wire that is in series with the light bulb to be wrapped around a steel nail and placed in close to a "normally open" reed switch that operates turning on the battery. The reed switch turns on the battery when you were slowing down as the alternator output lessens. The magnetism of the electromagnet crudely made with the steel nail let the reed close when it slowing.

If not having a rectified voltage to DC with a diode to keep the DC from the battery from going into the alternator and AC low volts at slowing speed from the alternator into the battery, I just though to have two bulbs.

Have the alternator with ac on one bulb and the battery with this nifty automated switch to turn on the second bulb run from a battery all together separately. The alternator bulb starts to dim as you slow down and before it goes out completely, the bright battery driven DC bulb comes on. The AC bulb from the alternator is also still slowly dimming till it is out and you have kept the circuits isolated from one another.

Thanks to Bob Kennet from writing back to NV to answer this and I embellished on it. Note Nuts & Volts does give disclaimer NO GAURENTEES on the upper left side of the page.

Measure Twice

I just remember this is just an engine swap, that the engine mount platform is already done. Is this a kit clamp on engine platform or did you make the clamp on, or is it your welded? It does look nice and sleek.

I welded a platform but fitting the engine meant that it sat tilted back and I made a few adapters on for making the carb level so the fuel bowl float would be level. I had a bit of a time with some redesigning my rear wheel clamp to spokes washing machine pulley drive so that I am getting back on track now finishing the build.

Measure Twice