Chinese quad/scooter rectifier/regulator teardown with schematic

Aside from the fact that this module was potted in sand with a thin layer of resin on top, the circuitry is rather minimalist too.
I was expecting something a bit more sophisticated for the battery charging than a diode.
The other shunt circuitry for the lighting circuit is also a bit strange. I know it's fairly common to use shunt regulation on bike alternators, but it seems to me that it will result in excessive heat from the alternator or at the very least, an extra load on the engine.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
www.bigclive.com/coffee.htm
This also keeps the channel independent of KZbin's advertising algorithms allowing it to be a bit more dangerous and naughty.

[@AttilaAsztalos]

Come on, it's obvious - the sand is simply a generous amount of _spare silicon_ just in case you need to repair your triac or something...

[@aterack833]

I really want to see some warranty call where they say that to the customer now

[@hdezn26]

@ss ss Maybe its to spawn a creeper have lightning strike it and set it off? I know thats a bit random.

[@davemcgaffney9401]

What's cheaper silicon seal or sand? The sand is probably used to fill the potted device and then you don't have to use as much silicon sealer to pot it... Remember they are going to make it as cheap as possible...

[@Lucien86]

@@davemcgaffney9401 It also makes it feel more heavy. Heavy = expensive..

[@stupot_64]

Being filled with sand seems to be common in quite a lot of cheap stuff trying to appear as good quality. I took apart a rechargeable C cell to find it containing a AA plus sand to add weight.

[@marcusbadoyo3112]

I took apart a 18650 cell that showed 0 volts from a fake xiaomi power bank and it contained nothing but sand. There were three other 18650 cells in it with measured capacity between 300 and 700 mAh.

[@wsketchy]

@@ge5645 i don't have a fuji camera checkmate liberals

[@BoB4jjjjs]

@Matthayi Naalaaman Just add water for good effects!

[@jonnoMoto]

They used to do this a long time ago with usb "ssds". Was a usb pen and a lump of steel inside the case.

[@herauthon]

or just a cheapest way of fire-extinctionizer..

[@nirodper]

These are known as "half wave" regulators and yes, it isn't suposed to have a full bridge rectifier as it is useless. Originally fitted on all honda (and chinese copies) style motorcycles after the 70's, when the battery used to just have a selenium rectifier. As the battery and light share the same coil, the battery voltage is kind of regulated. Some bikes even had a 10w resistor that the light switch powered when the headlights were off to improve regulation. Later you have "full wave rectifiers", with only one coil, floating from chassis ground to allow the use of both positive and negative half waves. This allows for a bigger battery for electric starting. You can also turn on the lights with the bike not running. There are of the 4-wire variety (like the one you showed, it's not good to confuse them) and a 5-wire one, with a switched voltage sense to eliminate quiescent current (also the battery won't charge if the bike is stolen)

[@gordonlawrence1448]

I didn't realise they had gone that "bare bones". My last big bike (GSX1400) had a 3 phase alternator which I swear looked like it was originally designed for a small car.

[@nirodper]

@@gordonlawrence1448 well it's 50+ years old tech, nowadays it would have a couple microcontrollers and CAN comunication haha

[@fellenXD]

Big thanks dude! I fitted one of these bad boys to my moped, as it didn't have any real regulation originally. I wanted to be able to run 12v led lights and stuff, but it kept frying any electronics i connected (except my Wish $2 led rear light lol). I'll try to have some sort of load on it at all times and see if will work properly.

[@SidecarBob]

@@gordonlawrence1448 Real bikes do have more sophisticated charg8ng systems. This stuff is for the cheap disposable ones they sell at hardware or department stores that people buy to see if their kids are really interested without paying for something good that will just end up rusting in the yard.

[@iamblaineful]

This is why they always said "NEVER RUN YOUR BIKE WITHOUT A WORKING HEADLIGHT". You either wouldn't charge or would over charge depending on the implementation. It was a bad design, but you can thank Honda for that.....simple, cheap, and relatively reliable with easily sourced parts....ain't no fancy IC's going on here kids, just the basics.

[@hlavaatch]

Maybe the sand is part of chinese hourglass based timing circuit :)

[@Herbal69]

As the Magneto turns, like sands through the regulator, so is the day or two of our quads.

[@acbthr3840]

What

[@mycosys]

i'm sure theres something that continues that, but that was always the point where i changed the channel XD

[@twostime]

Something poetic about that ;)

[@asrcav8r]

First thing I heard was "as the stomach turns..."

[@tomgucwa7319]

It's from a very old tv show - daytime -drama...as the world turns....I recall it from ..1965 black and white...63...1 pm ..it would have been the show , interrupted , when walter cronkite ,reported on a bad day for jfk ,in dallas

[@hullinstruments]

Hey Clive if you like this stuff I can send you a mountain of it. I go to my buddies electronics recycling place three or four days a week to poke around and they get tons and tons of those cheap Chinese four wheeler’s, Dirt Bike’s, and motorcycles/crotch rockets. The wiring harness simply zip tied to the frame and some of them even have a knock off “brain box“ (ECM). I’ve dissected many of them just to check them out. I keep a modified toaster oven for help with depotting, and various harsh chemicals in different containers. Most of which are kept outside away from the shop and the departing definitely has to be done outdoors! The departing set up isn’t for this kind of cheap module… Because they really aren’t worth the time other than when I dissect them for fun. But I’m always being asked to repair industrial boards that have been parted. Companies like caterpillar bulldozers, miller and Lincoln welders, and many automotive ECM‘s are always parted with the nastiest and most difficult stuff 😆 I always avoid jobs like that. But if the customer iinsists and we absolutely can’t find a board somewhere online… Then I charge about 10 times my normal price 😂

[@COBARHORSE1]

Potted, not parted, I think you mean.

[@otm646]

Where is this heaven that has endless cheap mini bikes and ATVs?

[@mattrockman1028]

@@otm646 yeah what the hell but then I might keep that kind of info a secret too LOL

[@ckm-mkc]

You should start a KZbin channel, there is an audience ;-)

[@tbelding]

@@otm646 - It's probably where Mustie1 lives, in Nowhere New England. You can't find dumped/free motorized equipment in Houston, that's for sure.

[@alexbowey2760]

The solution to overcharging batteries on older British Bikes was to use a ZENER DIODE with heat sink ,the lighting circuit was tapped from part of the alternator windings.

[@NuttyforNissan]

I was thinking the same thing.

[@graemezimmer604]

Yes, the basic bike alternator is current limited, so a simple shunt regulator (via a power zener) is all that is needed (plus there is no field winding to regulate). However, a zener will get fairly hot, so it looks like a Triac has been substituted to shunt the un-wanted part of the waveform (as it's either Off or On there is little dissipation). Note that while the battery is low, the battery itself shunts the alternator, so the regulator isn't doing anything. It's only when the battery is fully charged that the regulator needs to divert the unwanted current. It's not clear from Clive's circuit, but i suspect that the full wave bridge is there so the Triac can shunt both halves of the waveform.

[@ianc4901]

@@graemezimmer604 An alternator will have 3 separate coils and produce 3 phase electricity, these can be turned on or off. Some old British bikes had a switch position which turned on the third winding when the lights were needed so the battery would always receive enough current for charging. The system Clive shows only has 2 coils and only 1 of them is for the electrical system, it just barely has enough power to run lighting and charge the battery at the same time, I suspect the odd waveform is an attempt to conserve power by quickly switching between battery and lights.

[@graemezimmer604]

@@ianc4901 What is your point? Bikes (and other small engines) have used Shunt regulators since year dot. Are you trying to say that they don't work?

[@steverpcb]

The folks at meriden used to play cricket down the gangways with zener diodes :(

[@danp3653]

The lighting winding is used for the headlamp which is the biggest power item. This means the secondary coil and rectifier can be much smaller, cheaper, lighter etc. The big power incandescent headlamp doesn't mind being AC so long as it's voltage is capped at about 13.5v. That is why at idle when the headlight is on on a bike you can often see the lamp flicker slightly.

[@jg374]

The quad bike I have worked on uses a 3 phase version of this for charging the battery. Due to the large amount of heat it produces, we have had several units fail. On closer inspection, the last two that have failed have also been mainly filled with sand and only potted with resin on the last few mm, supposedly for cutting costs even more, which wouldn't help heat transfer to the aluminium case. Generally when they fail, either the triac (or equivalent component) fails so no regulation happens and the battery is overcharged or the rectifier diodes go open circuit and charging stops all together. The rectifier diodes failing open circuit or the regulator being disconnected has interesting results as from memory, the cdi unit uses a connection to one phase of the stator to drive a voltage doubler to get it to the high voltages required. This relies on the rectifier diodes in the regular to reference this voltage to ground, meaning the ignition system won't work if the regulator fails open circuit or is disconnected. Once the bike is running however, there must be enough capacitance in the wires or some other factor that it will keep running without a regulator, leading to much scratching of heads :). The last time we replaced the regulator, we looked for a different branded one with the wires coming out in a different order of colours, so hoping it is built a bit better. We are also running the headlights on all the time to try to reduce the load that has to be shunted by the regulator and not leaving the engine idling for long periods of time. Fingers crossed it keeps working. EDIT: Remembered that the signal to the CDI unit is just one phase of the stator, not a dedicated coil

[@bigclivedotcom]

I depotted both the regulator and CDI module (complete with sand). Videos coming soon.

[@mycosys]

There have been a few comments that this design needs to be run with the headlight on all the time or the regulator and mag overheat and can even blow coils

[@Cutehuskyshorts]

@@bigclivedotcom ok disassemble a cooker

[@Cutehuskyshorts]

@@mycosys 5 hours ago clive commented

[@jg374]

I probably should have mentioned that this is an agricultural 1980s honda. There is another comment on this video that mentions full bridge rectifiers and I realise this is the case with this one, making it a little different to Clive's. The stator is 3 phase and is rectified. The voltage monitoring and clamping circuit is after this. The ground is connected to the vehicle's ground and the positive to the battery. Depending on the cheapness of the regulator, there may be another positive that powers the voltage monitoring part that is switched by the ignition. The headlights in this bike run off the 12v supply without any dedicated part of the stator or tap, so can be switched on and off, although leave more power for the regulator to dissipate when off.

[@otm646]

I am rebuilding an '80s three-wheeler and replacing all of the wiring and ignition components. Good thing I didn't buy this one, I was looking at it last night.

[@rdflo6739]

I was looking into similar stuff whilst rebuilding my '90's Yamaha. I was surprised to see how cheaply the original rectifiers were made. Basically shunting out the 3 fase generator to try and achieve some level of battery voltage. This causes great stress on the windings on long trips as a lot of heat is generated. Interesting to see that the Chinese managed to reduce the design quality even further... ! I'd love to see s teardown of a Japanese rectifier regulator! Thanks Clive! Love your accent, grew up in Edinburgh in the 70's...

[@joebarnett8640]

This type of generator, the same as a bicycle rim generator, is a current source not a voltage source so to turn it off you short circuit it. It still produces it's rated current but with no voltage there is no power. If you were to open the circuit at high revs there would be very high voltages on the coils.

[@graemezimmer604]

This is correct. Plus there's no field winding to regulate anyway.

[@bikefarmtaiwan1800]

Hey Clive - thanks for the video . I have been using exactly these guys for around 30 years and they are amazingly dependable . They do not tend to fry the battery and charge well enough . As a few others have said the lights get dim at idle but the battery charging is actually quite strong at idle and dips a bit as revs go up then stabilizes . The green to earth goes through a ceramic dump resistor 5-8 Ohms on my bikes , don't know if that is interesting for you . Thanks again for so many great videos and your smooth presentation style - much enjoyed .

[@moi01887]

Years ago I owned a 1971 BSA 250 cc single-cylinder motorcycle. As with many smaller bikes at least at the time, the alternator effectively consisted of a permanent magnet rotating within a coil. Its output was fed to a selenium rectifier, and the "regulator" was a 50-watt zener diode. It did have a battery which of course provided some voltage stabilization but that was the entire charging circuit.

[@joshmyer9]

This has inspired a new game idea: "Here's a waveform, draw a circuit that generates it." Because if you'd shown me that output waveform, I would've had to do some thinking about it. (In the linguistics department, they would sometimes have lunches and play a similar game. They'd hand out a printout of a spectrogram, and the game was to figure out what the person was saying. You had to figure out the sounds, then figure out the language, then translate. Linguists are a strange bunch, but fun at parties, especially linguist parties.)

[@phonotical]

Like an autogram!

[@evilgibson]

Zachtronics makes games like you said in the form of Shenzhen I/O where you have a lot of tasks simulating wave forms

[@joshmyer9]

@@evilgibson Ah, neat! Thanks for mentioning it. (I'm not allowed to have Civilization or Zachtronics games in the house, but maybe I'll pick that one up over one of my breaks from work later this year. I just have to make sure I uninstall it before I have to be a functioning member of society again.)

[@TheRailroad99]

Just take pSpice / LTSpice (a circuit simulator) and start designing analog synths. Analog synths are fun, and a great way to learn A LOT about analog circuits. Analog stuff amazes me. Most designs aren't "text book" and have many little quirks to reduce component count or make them better. Theres so much more knowledge needed to design an analog circuit from scratch compared to a digital one.

[@evilgibson]

@@TheRailroad99 that software is not what the OP was asking for.

[@hmpeter]

That circuit concept has been used widely in simple mopeds and scooters in the last 30 years or so. Simple but effective, cheap to make and very durable. I like it. I built a couple as spare parts for my broke fellow students in my youth. ^^

[@SunnyJulienDivine]

6:00 The magneto can be crowbar shunted on higher rpms because the frequency is higher and therefore the impedance rises, too. Also the filaments of the bulbs won't flicker when a high frequency spiky voltage is applied (1500 rpm = 50 Hz, assuming a 2-pole stator with a 4-pole permanent magnet rotor) 2:32 The same reason applies to charging the battery, higher rpms let the impedance rise and limit the current into the battery. When the lower part of the winding is shunted (chassis-yellow) the upper part (yellow-white) won't add much voltage to the overall output.

[@gingerelvis]

It would be interesting to see a comparison between a cheapo reg rec and one from a Japanese manufacturer, especially as they can be prone to failure over time.

[@sidecarbod1441]

I agree, I hope that the Japanese ones have a proper regulator circuit on the DC side. I had no end of issues on an old Honda MT5 which only had a single diode on the DC side, there was no regulator on the DC or AC side. It boiled up my modern sealed battery which caused the DC voltage to float up to some really high level, it then blew all of the DC powered bulbs and the flasher unit! The AC voltage also went high and that blew the AC powered bulbs. In the end I fitted a 4 pin 6v regulator unit off a later model, (SH570-6), the DC voltage now sits at about 7.8v which is still a bit higher than I want but it was up at around 9v when it was running with just a single diode, (no wonder the battery boiled!), I guess this must mean there is some form of regulation going on.

[@gingerelvis]

@@sidecarbod1441 damn that's an odd failure, usually they just die on you miles from home

[@LasheXX]

@@sidecarbod1441 i have same problem on gy6, all my electronics are BLOWN(flasher relay, blinker bulbs , tail/headlight, dashboard, speedo,odo..etc) and battery. idk what to do at this point

[@sidecarbod1441]

@@LasheXX I'm not sure what a gy6 is, if its an old bike with 6v electrics then you need to find out whether the AC is just rectified or whether it also has a regulator, really you need a reg/rec unit. I have also given up using sealed batteries on my moped, I now used an old style lead acid battery that I can top up if required, it seems to be able to cope with the 7.5v that the charging system puts out. When the Honda MT5 was in production it was fitted with a lead acid battery.

[@sidecarbod1441]

@@gingerelvis Yeah it was annoying but at least the bike got me home!

[@ginamiller6015]

This style of “regulator” has been around for a long time. Years ago I discovered these brute force shunt style clipping regulators on my dirt bikes. Apparently when you fire the thyristor abruptly, the surge of current causes alternator field to collapse. This effectively unloads the alternator and limits the system voltage at the same time. I had originally thought this would waste power and make the alternator hot, but it doesn’t. Crude, but effective.

[@theshaddowaust]

Almost that same Reg was on some outboards, as I had one on mine, I changed it 2 days after I started to smell boiling battery, I had done a check on the old one before removing and found it was pushing 18v into the battery, the new one has a actual output Reg rated max of 14v which has made t safe for all connected to it.

[@baronobeefdipyes5181]

My ignition control module on my 79 granada was potted that way, and it did in fact have issues with moisture

[@johnjones5943]

Hello Clive the way the bigger bikes control and rectify the voltage is very similar to this except they usually use a 3 phase alternator with 3 thyristors one for each phase the voltge is then rectified by a 3 phase rectifier and the voltage sampled and each phase is then shorted by pulsing the thyristors on and off this then regulates the output voltage to around 14 volts this then controls and charges the battery. Its a bit of a sledgehammer way of doing it but it works just fine. It also does not overheat the alternator windings because as soon as it shorts out the alternator there is no current flowing as it is fully shorted and in theory no current flows and therfore no heating occurs during the shorted out pulses. Thanks for the channel by the way all very good stuff.

[@georgebayliss3291]

You know, ever since starting to watch ElectroBoom many years ago, I can't stop hearing: "FULL BRIDGE RECTIFIER!!!" inside of my head everytime someone mentions diodes or rectifiers.

[@hdezn26]

I hear rectumfryer, only because of our favorite kanuckistanian, AVE .

[@georgebayliss3291]

@@hdezn26 That made me chuckle, forgot about the alternative version!

[@michaeltempsch5282]

@@hdezn26 ...and when I hear rectifier I immediately bounce back to BigClive, testing that electro-play unit... Edit: awww, didn't notice that auto-mangler turned rectumfrier into rectifier, making things a bit nonsensical 😐

[@bjornholmqvist3230]

hahaha yeah same here!

[@iangraham6730]

Nice topic, and nicely presented.. hope you do more on automotive component's Clive 👍🏼

[@donkrapf]

The old incandescent bulbs work fine with the strange wave-form. I upgraded my headlight to an LED rated for DC or AC (internal diodes?) and it worked but flickered. I upgraded my tail/brake light to LED and the brake portion died. Who knew that a single bulb was powered partly by DC and partly by AC? It didn't matter as long as it was incandescent. I eventually replaced the regulator/rectifier and modified the stator to achieve an all DC system so that I can run all LEDs now.

[@frogz]

i feel absolutely naughty being here at under 1000 views, thank you clive!! you should buy a 49/66 cc chinese "happytime" engine kit as they are known in the motorized bicycle circles, they are fun as hell for the brief period between when you first get them and are still working the kinks out and when the engine is on it's last legs, you usually can get 2-3 years of life from them although i've had as few as 3 months before a engine ripped itself apart internally! my current build is on a 24 inch frame, totally hacked apart and ghettorigged custom just to fit :D ....now to fight myself not to buy a wiring loom... i dont need it, i cant afford it, i just want it..

[@oldbatwit5102]

Not sure about The Isle of Man but in the rest of Britain motorised bicycles are illegal unless used on private land.

[@johndododoe1411]

@@oldbatwit5102 Unless they pass the type test and MOT, obviously. Famous models like the Norton would obviously be built to do so.

[@fanplant]

my friend had an early 80s suzuki and his dad put a headlight switch to shed load while cranking but if you left the load off it would boil the battery. Or that's what I remember. I learned back then not to try and troubleshoot bikes the way I know cars.

[@ssgeek4515]

Umm.Im no electrician but I believe bikes can rev quite high causing over voltage from magnito. Your headlamp would create a voltage dropper as the element heats (higher resistance) it's a simple way to limit power. Method used in audio to protect speakers from too much voltage (watts) to drivers. Starts to glow when peek is reached

[@fanplant]

@@ssgeek4515 I remember seeing the schematic and I think it was more than a dropper but relied on the expected load.

[@markvandesande8855]

Ahhh thats why when there wet it reads like a large capacitor. I love pointless half wave noisey rectification. I remember my bike light strobing making me fit fall off the bike and waking up in a ambulance. Expensive crap exposed for what it is. Cheers Clive 🤪👍

[@SodAlmighty]

Perhaps if you're strobe-triggered epileptic, you shouldn't be on the road in the first place? Just a thought.

[@markvandesande8855]

@@SodAlmighty Erm how are you ment to know if it's the first time? Also i am no long epileptic it was a teenage thing.😉

[@SodAlmighty]

@@markvandesande8855 fair enough

[@derricksmiles6624]

It looks like it's for a 6v system hence the 7v charge limit, your close with the reverse engineer but bridge rectifier will create an noisy dc power feed due to no cap, when high revs it will clip/shunt at 7v. This is why most peds/scooters lights pulse on idle.

[@killcar5nbike2]

If they'd used a Triac shunt a bridge rectifier trigger circuit could limit battery charging voltage too. These were fitted the the Honda C90 when it went square headlight (well a variant of this) as the resistor based ballast system was prone to allowing the bulbs to blow. The first 12v CDI C90 with the round headlight just had a zener clamp and 1/2 wave rectifier based regulator. Honda kept the charging system as cheap as possible. The AC fed lights and battery as part of a ballast allows a better power factor load on the stator so allows a smaller stator plate to be used. With the lights on the stator is sized to be just about outputting at its VA rating so the regulator and battery have a pretty easy time.

[@dimitar4y]

classic china, fill it with sand to make it heavy to "feel premium", and then put on resin.... Decoratively..

[@rujor]

Well, you could make a sealed product, and still be able to fix/debug it in case og failure 🤷‍♂️. I could find the idea useful for version 0 hardware.

[@TheStuartstardust]

I have seen an ipod made like this on market 😄 ..but most likely not original 🤣 ..or🤔

[@michaelfisher9671]

Sand is a good conductor of heat but not electricity. Wouldn’t that make it quite a good choice, if well sealed?

[@walterk1221]

@@michaelfisher9671 wrong! Sand is a poor conductor of heat.

[@TheDutchShepherd]

@@walterk1221 that's why I burn my feet on the beach in summer?

[@JWH3]

Well there is all that sand in there to help spread out the heat, not sure how much that helps, but the thermal cycling along with ambient air pressure changes is gonna make that thing breathe really well so you're probably right about it being a moisture trap.

[@truckerallikatuk]

Hey Clive, could you strap a magnet or 2 to a drill bit and spin that with an electric drill in the magneto to simulate things?

[@ThriftyToolShed]

Great video!

[@OneLegged-honda-mechanic]

Eric O recommended this channel. I just subscribed 👍

[@wicks7581]

Bloody hell, I guessed it was going to be low rent but wasn't expecting it to be this bad! I'm glad the majority of these machines get briefly abused, followed by being left for dead when the owner gets bored of it.

[@amojak]

The battery is regulated by the very shunt regulator you detailed as it shunts the entire winding. The bridge rectifier is because with lights off both sides will be full voltage.

[@Witschor]

Hey there, its completely normal Design. My 1984 yamaha xt 600 has also sand in its cdi box. That Thyristor shortcut design is also the same , even on the later XT 600e Models with elelctric Start and 3 Phase Alternator with 3 Thyristor shortcut design and zener ignite system even without extra switching Transistor. Almost all Japanese Bikes are regulatet this way , but without ac Lights. And yes it collapses the Magnetic Field ot the Alternator , so the Thyristor is not killing the hole Energy,the altornator is able to produce. Greetings from Germany

[@Quincy8Boy]

I just went on a two month adventure replacing my motorcycle regulator/rectifier & stator. It was either deal with cheap, non-functioning parts or pay 10 times the price for OEM. 2000 Suzuki Marauder, VZ800

[@Electronzap]

Good video!

[@justinandresmooi7758]

My previous comment stems from I am looking to use one of these to rectify ac to dc off a snowmobile to power a led light bar. With a capacitor after the rectifier to level out the power. Needing to know where to plug the load, load ground, supply and supply ground. Creating a complete loop since I am using the stock wiring up to where the stock light would have been.

[@Amin_Amini]

Perfect I need this ❤

[@jakp8777]

I’m amazed you were able to un pot it and not destroy it when it was filled with non reworkable potting compound.

[@brandonbrandon749]

I did the same with just a screwdriver praying very carefully for like an hour

[@MostlyInteresting]

Way back generators on small engines were just dropped across lead acid batteries or a bit later alternators were rectified and the battery just loaded it down. There was no attempt at any voltage or current control. This works so so when the charge current was only a few amps and the battery was primarily for starting. In some cases a separate coil was used for the biggest load, lighting, to limit the current to the battery. You had to top up the battery with water often and also charge the battery off the mains now and then if you wanted it to live. As the current drain went up in boat motors, power equipment, motorcycles, this scheme was not going to work. So the next step was to put a voltage clamp right after the rectifier. This was a big fat zener diode or a linear circuit that was basically a high dissipation clamp. This keeps the load constant on the alternator, maintaining a predictable idle speed, since small engines don't have the idle torque to deliver much power at idle. But it is very wasteful. Later versions used a SCR or MOSFET and PWM control to short the winding's out. Instead of the linear circuits. Large bikes usually have a 3 phase alternator for more power in the same space. This was the case up into the 90s, till bikes had a ton of power hungry loads and they also started having EFI which can regulate the idle speed. The bigger bikes then got field regulated alternators just like cars at this point.

[@ErikMinecraft]

Some years ago, I had problems with my old 70´s moped (better call it Mofa- Motorisiertes Fahrrad) with an completly unregulated 6V magneto, that the lightbulbs would constantly burn out. I then tested a regulator from a scooter wich regulates anything higher than 12V to 12V´s, wich stopped that. But I always wondered how these regulators worked due to it needing a chassis ground. Oh and there is very nice webside wich goes into great details about 70 and 80´s Magneots and regulators wich where used in german mopeds in that time.

[@roboman2444]

Would the "shunt" also help keep the battery from being overvolted? Since it is a full bridge rectifier, it should do the same behavior on both positive and negative peaks of the sine wave. I guess the thyristor is in the wrong way for that to work, though.

[@anthonywilson4873]

Light run ok on AC no need for rectification but voltage needs trimming to stop bulbs blowing. Charging a battery need rectification the quad I am working on for friend has a three output wire. Ignition is separate inductive pickup. I understand a bridge rectifier. The circuit you have drawn reminds me of circuit on standard alternator. A zener diode breaks down over its voltage threshold. The allows current flow to base of delicate sensitive transistor., the transistor switches the base of a power transistor which disconnects path switching of rotor coil reducing the output. Zener diode switches closed again turning off delicate transistor which in turn powers up the power transistor reapplying ground to rotor. Basically a sensitive switch operating a heavy duty one all decided by zener diode switching. Almost like old school regulators on dynamo which used coil magnetism to move switch basically buzzing away regulating voltage and current.

[@blazeykk]

This one is full of electronics! I had one with only one diode inside between white and red. And some sand under the sealing mass.

[@MrHanichak2]

Personally for my experience with my three different scooters the first being a 50cc 2-stroke and the other two being four strokes the battery really never retained its charge too 12 volt or higher it seemed every two or three months during the summer I would have to recharge it just to make sure that I had enough energy to electric start the bike and keep the headlight bright enough for me to be seen at night and to be able to see!

[@JonnyMudMower]

I’m literally going down to my shop to see if I have a sandy one right now lolol

[@Nathan0A]

I had the voltage regulator fail on my late 90's yamaha FZR motorcycle once, I was facing a garage door and very quickly my headlamp got very bright, and then flashed every color of the rainbow at insane intensity before going dim and the bike dying. The headlight's behaviour is what alerted me to the regulator failing

[@paulmccoy2908]

Wouldn’t shunting the coil on that half of the sine wave change the voltage on the charging current half of the coil? Because the center tap is now the ground reference?

[@dfpguitar]

playing devils advocate, ultra high voltage/current fuses and construction site transformers in the UK are filled with sand too, because it's something that doesn't catch fire

[@stevefriedl3983]

High-rupturing capacity fuses in multimeters have sand-like fillers too.

[@stargazer7644]

Hrc Fuses are filled with sand to quench the arc when the metal vaporizes.

[@liamofthornhill]

That same unit is on many bikes from China and surprise surprise they always develop electrical gremlin when you wash them or ride in lots of rain

[@raygale4198]

The main issue is that the magneto is a permanent magnet DC generator, it works flat out all the time and if not loaded/shunted will produce voltages well over 60 Volts at high RPM. That was one of the early Honda tests, unplug harness rev engine and measure for around 60 ish volts at the connector. So yes it's an incredibly inefficient system still used by 90% of bike makers today. Manufacturers today are now having issues caused by LED lighting, they have had to fit regulators capable of absorbing higher power due to the low current draw of the LEDs. In the case of the 2020 Honda cmx500 with LED lamps they have completely rejigged the harness so the regulator hangs out underneath the bike to try and catch cooling air, previously on the filament lamped models up to 2019 the reg was under the seat.

[@menombakglobalis]

the solution is use dynamic_magnetic_field produce by controlled_coil...

[@marcellucassen8033]

On a Honda (moped) bike which is a 6 volt system the battery is charged with one diode in series (same as schematic) and the 'yellow' wire powers the headlight only OR when switched off goes to a load resistor similar to the resistance of the head light (maybe a bit lower actually) to prevent over voltage going to the battery? so no voltage regulator to be found or needed apparently? (the magneto setup is the same only 6 volt instead of 12 volts)

[@imark7777777]

We got a house that came with a riding lawn mower trying to troubleshoot it it's very weird even with the wiring diagram for me to figure out so yes vehicles are weird they have both AC and DC and I only recently found out that a car's alternator is AC with a bridge rectifier that doesn't necessarily filter out all of it to dc. Oh yeah they also use the DC battery as a capacitor to smooth out the alternator which is why you shouldn't run without the battery, however newer Vehicles apparently turn off charging from the alternator after the battery has topped off so trying to run a large load like an inverter could theoretically burn out your cheap alternator.

[@spokehedz]

Things for these kinds of bikes are "built to a price point" and by watching this I can see that the bottom isn't too far off from what we have here... 3:33 - that diagram is almost a bit too naughty for youtube. XD

[@pokojnitozo2360]

That should be TRIAC, not thyristor. It clip both sides of sine wave. So that is reason why they use bridge rectifier. And trigger only with positive voltage on gate. That is so called parallel regulator. It short circuit coils. So on lot bike it regulary overheat, or coil burn out, if you drive it with headlight off. I have collection of schematic for CDI and regulators. If you want I can send it to you, so you can see different solution and compare it... It is usually for old bikes, some of them is for 6V systems.

[@Peter_S_]

A triac is a type of thyristor and was also known as a bidirectional triode thyristor in times past. 😉

[@nirodper]

never seen a coil burn, the coupling is not good so when you short it it doesn't really dissipate that much power, it really behaves kind of like a current source. Also properly potted regulators barely heat up if at all

[@pokojnitozo2360]

@@nirodper I had one coil burned on my NSR 125. And 3 or 4 regulators in 2 years. One on CBR 600. Both are very similar. And are 3 phase... And after few hours of driving, it is hot enough to burn you.

[@pokojnitozo2360]

@@nirodper Yes, but symbol it is different... And in regulator should be bi directional, and clamp both sides of sinus. Not one.

[@phils4634]

Seeing how that all works, it wouldn't be too difficult to accommodate some decent circuitry in that little box - there is after all enough space. Decent charging, regulation etc - probably all available via EBay / DX / Banggood so relatively inexpensive, should anyone feel the need to experiment!

[@Derundurel]

Are you sure the thyristor isn't a triac? The circuit looks as if it might work on both half cycles if that were the case. You could try this circuit by connecting it to a lowish voltage (say 24 V) AC supply via a suitable current limiter. This could be a resistor or filament lamp. You could then see what is happening with your oscilloscope.

[@gordonlawrence1448]

That was even more bare bones than I expected. I was expecting the old "amplified Zenner" type circuit.

[@lovotcore6946]

the lights don't need DC, I was more expecting a triac so when the voltage gets too high, it cuts out, maybe throw a little cap and a choke in there to smooth it out a bit.

[@BongbongA99]

I wondered if some magneto coils are arranged such that each one is referenced to ground (instead of series as shown). Also, since the thyristor essentially shorts the lighting supply when the switching threshold is reached, I wonder what current will flow and whether or not it's stressing the thyristor and/or magneto and/or wiring. I am searching for a solution that can be applied to a 6V system, so I guess (just for the lighting really as the supply to charge the battery seems to be ok, albeit rather crude - just a single diode as per your drawing. So far no boiling etc occurs).

[@mcdon2401]

I've got 2 blown reg/recs off my Triumph. Tempted to hack them apart to see where the differences are between the cheapo EBay version, and the eye wateringly expensive Triumph part.

[@bigclivedotcom]

Probably not much.

[@gbraadnl]

Just a sticker on the outside that says Triumph for the expensive one and Victory for the cheap one

[@robertpepperwolfe7256]

this is VERY useful info. PLEASE do the cdi next. this explains why my battery exploded once. long ride, stopped for fuel, and BOOM when i tried to start again. im guessing hydrogen build up from over charge? i checked it and it was putting out 60VDC at around 1/4 throttle. never figured it out, even the "replacements" didnt work, just went with leds and plugged in a charger every night.

[@bigclivedotcom]

Coming soon...

[@TheBlibo]

Hi Good evening You gets wet you pay for, all the kaswasakies I have owned use alternator that are similar in construction to a conventional car unit and output controlled in the same way The old triumphs used permanent magnet alternator and just had a zena across the output of the rectifier. I think it's the cheap Chinese stuff that isn't designed properly Keep up the good work

[@babelfishdude]

Many scooter manufacturers simply state to not fully charge the battery. Some people can actually drain their scooter and keep it at around 40%, only charging to 90% or full just before use (an outlet with a timer set to two hours is usually enough) Which is the best way to keep a lithium ion alive. Which is completely different than a cellphone, where you almost always keep it at 100% when not in use.

[@lovotcore6946]

Any reason a triac with a zener controlling it's gate wouldn't work? slap a rectifier on the output, a choke, and a cap to get smoother DC, run the lights and battery charging together.

[@mysock351C]

The bridge rectifier would make more sense if a bidirectional thyristor was used in lieu of an SCR. Then it would actually provide regulation since it would shunt the lighting winding section and cap the voltage the battery sees. Maybe they over-skimped?

[@XNeo27564]

Cool

[@FIXDIY]

What is this coincidence, I am now working on installing easy chips charging in a phone with a charging problem, the same piece that was explained in the video

[@GalvayraPHX]

There are some things I don't understand. How is there a negative component AFTER a full-wave rectifier? Also, it seems to me that the voltage divider leaves about 0.3Vin on the zener anode, thus the zener should be active with Vin > 10V. Wouldn't this clamp output over 10V and protect battery from overvoltage?

[@bigcheese781]

The sand is for safety, it's an HRC-regulator.

[@bigcheese781]

@chemical licker A fundamental category of electronic components are called "HRC-devices", those are safety critical and commonly filled with sand. Just use your preferred www search engine and look for "inside HRC-Fuse" as an example.

[@svoranger]

The alternator might have the overcharge protection built-in to it. Most modern-day alternators have the voltage regulator built in.

[@electroniquepassion]

👍

[@paultomkins9457]

Thanks for this. Explains why I seem to have had to replace batteries 3 times. Can anyone please link to a suitable good replacement ? Thanks.

[@qaisarawan93]

Also make a review of a 3 phase Chinese rectifier regulator circuit.

[@MrEdwardhartmann]

Could the first component be a triac instead of a thyristor? If so, would this circuit regulate both the positive and negative side to just over 7V - sounds good for a 6V bike system.

[@Rocco_v]

That's what I was thinking, the older 70's SkiDoo's had a similar regulator that shorts the magneto windings to not exceed 13 volts or else the headlight would blow, No battery in snowmobiles back then.

[@anonimuso]

Sad to say, 4 years of engineering school and had never heard the term 'magneto' before (except in the comics). Had to look it up and then "Oh, it's a generator". 🤦‍♂️ Maybe it's an American thing like not using the metric system. Also, thanks for the teardown and lesson. Subbed. 👍

[@MichalKobuszewski]

Think that's just the traditional word in this context, similar to the snubber cap in the ignition circuit being referred to as "condenser". That's understood I guess, as the basic design is like 100 years old!

[@tbelding]

A magneto is a specific kind of generator, using permanent magnets, rather than energized coils. Just claiming it's an American thing is like being upset with people for not calling a pickup truck an automobile. Because they're all the same. Now, if you spent that time as an ME, then I'd understand it. If an EE, not so much.

[@herauthon]

Does the Wrecktifier offer some protection ?

[@robertmason8341]

So I’ve got one of these Chinese scooters I’m trying to get roadworthy (I get it, that’s a joke kinda) and while I’m good with engines and wiring 12 volt stuff and understand basic electronic (just the basics) I’m not near as well versed as you guys (that appear to be EEs). So if anybody sees this I could use some help (I know it’s old thread). Engine runs fine, got that part under control. It just isn’t putting out anything from the charging system. I’ve replaced the stator and tested it while running and it’s putting out the requisite ac voltage on the yellow and white wires. 20-30 at idle and 60-70ish when revved up. Checking each phase (yellow or white) between ground. It uses that exact rec/reg (same size/plug) as far as I can tell externally. Same colors yellow/white/red/green. Now here’s where I might have been messing up all along and this only became evident after sharing you dissect the regulator and cdi and the harness video. I have hard wired everything the way I assumed it should go because someone had made a mess of the oem harness. Here’s my connections: Off the rec/reg Stator yellow to yellow on the rec/reg Stator white to white on rec/reg Rec/reg red to battery positive (fused 10 amp) Rec/reg green to ground straight to battery. Checking dc voltage at battery it just sits right at 12.7 doesn’t rise to normal 14 when revved like a normal working charging system would. What’s got me stumped is when I plug/unplug in the rectifier regulator with the engine running it pulls down the idle speed so I’m assuming it’s the load of alternator on the little 50cc engine. So leads me to believe it’s working. But no output at battery. I see the headlight has something to do with this from the video and the comments. Being i hard wired everything (cause the factory harness was butchered so bad) did I miss something that’s with the yellow coil wire from the stator that’s affecting the regulator and causing my problem? I’m used to working on big bikes from Japan and modern Harley’s that have three phase stators/rec/regs so this isn’t something I’ve encountered before (2 phase half wave whatever this type of system is called) Thanks for any help

[@justinandresmooi7758]

So whats the pin out for it then? I see you scribed a positive top left but what position are the others?

[@bazzmac4094]

Is Clive correct here?? I was of the opinion that the yellow and white wires are AC coming in from the stator, and that the Regulated DC comes out on the red and green wires ??

[@MarkTillotson]

The diode on the transistor's collector can also be removed if the bridge rectifier is simplifed as you describe I think. [ BTW the circuit is loooooooow quality IMO ]

[@kitecattestecke2303]

How do yo depot epoxy? Acetone? How? Didn't work last time I tried on potted led drivers... Do you use heat or ultrasonic cleaners?

[@McTroyd]

Hmm. Interesting. Could the shorting of the generator be an effort at braking? Or perhaps a (really rudimentary, ineffective?) effort at regenerative braking?

[@jaosnv2979]

Clive i have an ecu and 3 phase reg rec off of a yamaha the reg rec u showed is more of just a voltage regulater

[@jaosnv2979]

i have an internally shorted ecu for fuel injection

[@mlow587]

I got the opposite , dried it with 3 new rectifiers but only ever see 7 volts at output ?

[@teardowndan5364]

Unless stuff on the motorcycle/quad requires AC to operate, it would make more sense to do it like they do on car alternators: put a full bridge rectifier across the coils. With full wave rectification, the battery charging voltage can be a little lower (fewer turns on windings) and with windings not needing to handle short-circuit current ~1/4 of the time, they should be able to use thinner wire gauge too. You also get better energy efficiency and smoother operation from the engine by generating less unnecessary and irregular drag.

[@johngalt97]

The overvoltage is accommodated in the battery by electrolysis. Battery water maintenance is a thing for motorcycles with these crude circuits.

[@HarleyFXS]

What did you use to make the epoxy soft? I've been grinding mine out for hours. Got to the circuit board, it has two SCR's on mine, I did the lock test on them and both work. But all the other parts are a guess unless I can get the circuit board out. I tried alcohol and that didn't work.

[@bigclivedotcom]

Try heat.

[@tbthegr81]

Very cool, have wanted to see what was inside these as they keep breaking or producing odd results on my cheap china mopeds. Do the CDI next :D

[@bigclivedotcom]

Sneak preview..... kzbin.info/www/bejne/iGLao6Wpl5iFes0

[@alejandrotobienne8220]

Clive my question is. As these take up the duty of heatsinks. Would adding fans to help scrub heat. Help them last. I’ve got a cpu fan connected to a toggle switch wire tied to my Chinese Rectifier with great results. I’ve heard guys lasting years on same Rectifier with a fan. But most don’t want to attempt the job which I used the turn signal line on fuse box for current.

[@bigclivedotcom]

Airflow definitely helps cool heatsinks. On a bike the positioning could help if the unit is getting hot.

[@alejandrotobienne8220]

@@bigclivedotcom thank you 🙏🏾 testing on a 50 degree night only hit 75 degrees. On a 85 degree day stayed in the 120’s to 125 in traffic. Never went higher. Heat is the killer of electronics so happy knowing I’m helping it last a little longer at least.

[@marcioreis2648]

Hi, do you know how to depot a Shingenden voltage regulator, like FA020AA ? Thanks.

[@timothyeddinger7522]

Dear Mr. Big Clive, please excuse my comment ediquite as it is my first. I enjoy your stuff. I am a 55 y.o. manchild. Worked on autos all my life. It was explained to me at an early age that the SPARK OF AN IGNITION COIL is produced when the primary winding "collapses" over/on to the secondary. Say when ignition points open, the "back emf" from the deenergizing primary falls over the secondary. In short, the spark is produced when the PRIMARY GROUND CIRCUIT IS OPENED. CDI allows for an increase of primary voltage, thus a multiplication in the secondary. This is how I understand ignition coils work. (I've been wrong before) I did not grasp your explanation on this subject , though I usually do. THANX FOR THE FUN! Keep up the good work.

[@itsevilbert]

Since the frequency of the voltage is directly derived from the cycle of the engine, I'm guessing that quarter cycle with no load at all is the power stroke of the engine in a two stroke motor. You do not want any extra load at all to hinder the production of power on that stroke. I suspect that they are only charging the battery on the half cycle to reduce the fuel consumption. The magneto is maybe 6 per cent efficient. The energy to charge the lead acid battery needs to come from somewhere and the more power that is diverted to top up the battery ultimately the more fuel that is used. There is a back EMF generated by the coil in the magneto, so the higher the load the higher the force rejecting the direction of movement, so the higher the fuel that is used if travelling at the same speed. And I'd say that it is something similar to the lights, on the other quarter cycle. Again it is to minimise the fuel use.

[@kreynolds1123]

It would seam kind of easy and more efficent to do some basic voltage regulation with a buck converter.

[@qaisarawan93]

Good. Is it possible to use both coils and feed all its it's dc output to battery to charge battery fast and have lightning being run from battery instead of this pulsing ac? Any way to convert both the coils to charging battery fast.

[@qaisarawan93]

Also these Chinese cheap quads have half wave rectifier stator windings arrangements. There is a trick to convert them to full wave and have all charge go to battery and then run devices from battery. Please if you can make a video on how to do it. Will be a great service to all fellows.

[@modelsfirst]

Would a 100volt 3,700 or 5,000 or 10,000 Farrad capacitor be dangerous ? I need 100volt because a bicycle bottle or hub dynamo can output up to around 100 volts ac on very fast down hill descents. I plan to use it to make a full wave bridge rectifier as a smoother for my vintage bicycle dynamo lights (because modern mass produced dynamo lights are pig ugly) to stop the very annoying strobing that occurs with the AC & to hopefully enable the light to glow for a few minutes when stopped at traffic lights when the current from the dynamo is no longer flowing - the capacitor discharging into the load ( a 3 watt total of front & rear led bulbs). How long could I expect the lights to glow for before going out completely with these value capacitors please?

[@stuartsmith3084]

Would you do tear down of a Chinese air heater