aftermarket rectifier??

[cals400ex]

i see these ads for aftermarket rectifiers. i don't know anything about them. any good or gain from these? any advice would be great. thanks cal

[JDiablo]

what is a rectifiers?i never heard of it:confused:

[wilkin250r]

??:huh :confused:

Show me an ad...

[cals400ex]

i better check the add again. maybe i read the name wrong or something. :confused:

i will see what i can find.

[cals400ex]

here is an ad. i have a feeling they are not worth it. also, i am not sure how the batteries will like them.


http://gapracing.safeshopper.com/1301/4722.htm?707

[dustnyu17]

a rectifire is a metal object near the battry that changes the engery so it suitable for the igntion, i would never even think about changing that

[JDiablo]

9% horsepower gain:rolleyes: ....idk not for that much money i would keep the stock one unless if you feel you need it...that would prolly be one of the last things i would even look at changing....and prolly wouldn't even chane it so i say :confused2 :devious:

yeh it prolly wont be anything special. better things to buy.

[batgeek]

hehe we called them "rectum friers" in school!

[marty]

A rectifier turns the ac current from your stator to dc current. It may be possabie to get a nominal amount of power out but I really dont think so. When the magnets on your flywheel go past the windings on your stator it induses an ac current in the windings and the rectifier turns it to dc to charge the battery and run the lights. It disipates the extra current off as heat. Also on a 400ex the power for the ignition system does not flow through the rectifier. The ac current goes to the cdi diretly from 4 of the windings in your stator. I see no way this thing can give you more spark energy. Im not an engineer, my spelling gives me away, but I would not buy this if mine was still working.

[Hoodeye3]

IM GREEN WITH ENVY!
Great response Marty.... Its nice to know there are some out there to help us understand the specifics.

[MIKE400EX]

Anything to sell a part and make money. I still think some good ol' stickers will get you more power than that rectifier!:blah:

[cals400ex]

yeah, i really didn't know how they worked. i guess they just change alternating current to direct current.

i have talked to two people who put them on 400ex's and both recommended doing it. big gun said on the average 400ex you will gain around .7 horsepower. not much, but we are only dealing with 25 in the first place. i think i am just going to get an aftermarket ignition and i should see more benefits there than with the rectifier.

[moto93]

Taken from Procom Engineering's website:

Q: How to gain more horse power from our re-designed Rectifier ?

A: We built an extra sensor and switch in the unit. When the battery is near fully charged, the sensor instructs the switch to control the Magneto Rotor to run without cutting the magnet field. The rotor then runs lighter and saves the power to the engine. The engine gains more horsepower to drive your ATV faster!!!

Hope this helps,

[wilkin250r]

Originally posted by marty
Im not an engineer, my spelling gives me away,

I am. ;)

By now, you should already be expecting a long, technical post from me. For those that take the time to read it, you will learn HOW and WHY these rectifiers help your power. I think I'll try something a little different, and make several posts for the full explanation.

Many people don't quite know the difference between voltage and current, so I'll start there. If you already know the difference, skip to the next post.

Imagine you fill up a small 5 gallon air tank to 80psi. You have 80 lbs pressure sitting there, but it doesn't do anything until you hook up an output hose to it. You don't have to do anything to keep that 80psi in there.

Lets hook up a small sandblaster. That small sandblaster, lets say, requires 1 gallon per minute of air. You now have air FLOWING out of your tank, and your doing work. However, your pressure will drop quickly, so you need to put more air into you tank again, which requires energy. So now that you have an energy OUTPUT (sandblaster) you have to have an energy INPUT (compressor) to keep the pressure in that tank at 80psi.

The 80psi is like voltage. Voltage is basically a PRESSURE. Before we hooked up the sandblaster, we had 80psi (voltage) but we weren't actually doing any work. The air output to the sandblaster is CURRENT. If we only had 0psi, we woudn't have any output. Likewise, if we had 100psi, we would have MORE output. It's possible to have a voltage without a current, (just like having a tank but no output hose connected) but impossible to have a current without a voltage (you don't get any air output if you don't have any pressure in the tank).

However, what if we hooked up a bigger sandblaster? We would output the air faster. The amount of air is related to the pressure, but it depends MORE on the type of sandblaster. Same with current. The type of load is what really determines the output current.

What if we pressurized the tank to 3000psi. Pretend the tank can handle it, but what happens to the sandblaster? We blow it to pieces, along with the air line, it gets WAY too much pressure. Same with over-voltage.

[wilkin250r]

When you generate electricty, you have two variables to deal with, speed and torque. Speed controls the voltage, and torque is controlled by current. This is obviously a simplification, as there are many other factors, like number of coils and magnetic strength, but this simple explanation will work.


The faster you spin your generator, the more voltage it will create. If it doesn't have any output current, it's really easy to spin, because you are only fighting a small amount of friction. Now, let's attach a load and get an output current, and your generator will fight back. Now, you need to apply more torque to keep the speed up, because you are now fighting friction PLUS a force created by the output current. The higher the current, the more torque you need to apply. This makes sense, as you need more in power to create more power out.


When your quad is turning 7000rpm, you are generating WAY more voltage than you need. To protect all of your electronics, you have a voltage regulator that just dumps all this extra voltage, and only keeps 15 volts. This "dumping" of the extra voltage creates a high current, which requires torque to the stator to produce.

[wilkin250r]

The information that everybody posted so far is correct. The rectifier just changes AC voltage to DC voltage. However, these "new" rectifiers have a special switch, and that's how they help your horsepower.

Remember, from the previous posts, that creating a voltage without a current is really easy. You don't have any output power, so it doesn't require any input power, except to overcome friction. However, if you have a high output current, it requires lots of torque input to produce.

That's the basis of how these rectifiers help horsepower. When you are charging the battery, your stator is producing the current to the battery PLUS this other extra current that you are just "dumping", all of which takes energy from your motor. Even when the battery is fully charged, you are still producing the extra current that is getting dumped off. These aftermarket rectifiers have a switch that shuts off the extra current when your battery is fully charged. Now, you still have a voltage, but no output current, so it's not taking any power to produce. This means you have more power available to put to the ground.

How much power are we really talking about? In reality, not much. This extra energy that you are "dumping" isn't really all that much. I could see it being 1 or 2 horsepower, but not 5. So yes, it will help your horsepower, but not all that much, and only when the battery is fully charged.

[cals400ex]

nice write up. like i mention earlier, big gun said they get about 0.7 horsepower on an average out of one of these rectifiers. thanks

[wilkin250r]

Originally posted by cals400ex
nice write up.

Guarenteed cure for insomnia... :D

[marty]

How can you shut off a permanent magnet and a winding? Current is going to be induced if the magnet is spinning. Do thay just open the circut so the poor little electrons have nowhere to go? And does the magnet realy suffer more drag from higher electical demand? And 100 other questions now running through my head. I must medditate on this. Thanks fo keeping the gray matter working. marty

[wilkin250r]

Originally posted by marty
How can you shut off a permanent magnet and a winding? Current is going to be induced if the magnet is spinning. Do thay just open the circut so the poor little electrons have nowhere to go? And does the magnet realy suffer more drag from higher electical demand? And 100 other questions now running through my head. I must medditate on this. Thanks fo keeping the gray matter working. marty

You're still awake after reading all that?

You're on the right track, almost. A voltage will always be generated, but not always a current. Yes, they just open the circuit so the electrons have nowhere to go. If the electrons cannot flow, there is no current. (Current is defined as the movement of electrons)

Everybody has played with magnets, right? You can push them around on a desk and they will repel each other, if the polarity is right. This is how the generator will "fight back". Once you get a current flow, those electrons moving will create their own magnetic field that will "fight" the magnetic field of the magnets. The more current flow, the more it will fight, so the more force it takes to overcome. More power out requires more power in.

Like I said, if current is not flowing, you are not fighting that extra magnetic field, you are only fighting a small amount of friction.

So, to answer your question, yes, there can be lots of extra drag, depending on your generator size. Large power station require HUGE horsepower to turn those big generators. However, for your quad, it's really not all that much. I'd be kinda surprised if you saw a 1hp difference, and i'd be REALLY surprised if you saw a 2hp difference.

[marty]

I was kind of thinking that today. Once the current started to flow the windings thay would become eletromagnets. Or a simpler thought, for ever action theres a equal and oppisit reaction. You cant get output with out input. So for a race you could just unplug your rectifier. Trail riders could put a switch on the lead from the stator to the rectifier and control when you get that .7hp. Insted of when that rectifier decides it's ok. But be carefull thats a LOT of power. I may do the switch for when I try to race my friends, attack a too big hill, or to save some fuel on long day trips. Thanks for the input this could be a very cheep way to get some extra power wheen needed. marty

[wilkin250r]

It may not be quite as simple as that. I'm not sure if the rectifier and regulator are the same unit, and I don't have a full schematic in front of me to determine if this plan is safe or not.

In theory you are absolutely correct, but I don't have the whole picture to give you a definitive answer. Proceed with caution.

[zlam27]

wilkin - first of all, great write-up. i read it all and found it very informative/interesting. i dont know about everyone else, but electronics is one of my weak points when it comes to mechanics.

BTW: what kind of engineer are you and where do you work (if you can tell me/us). i am thinking of changing my major from diesel mechanics to mechanical engineering and i want to know what im getting into :D

zach

[wilkin250r]

I'm an electrical engineer, and I design magnetics. I work for a small branch of much bigger corporation, Tyco Electronics.

Mechanical engineering requires lots of math.

[redrunner]

Originally posted by wilkin250r
Guarenteed cure for insomnia... :D

j/k:D

Yeah were still awake, once again I love this chit! I am not an engineer but aspire to be a hands on one. I have some info on getting a Engineering cert by work related time and experience. Been to lazy or not inspired enogh to fill out the forms Hey I bought a 200 ton press from a Tyco plant in Detriot a couple years back.
Any way great post.;)

[duneittilludie]

I just recently put a big gun rectifier on my wifes 440 and i can tell you that without a doubt you can tell a difference in performance.It is kind of hard to explain what it does in terms of change but it makes your motor seem to get through the rpms faster or with less effort than without the rectifier.I too was skeptical but it only took a few seconds to feel that there was a difference from the stock rectifier.Those of you that feel that the rectifier is a waste of money should remember that a pipe on a 400 ex will give you maybe a two horsepower gain at best so a rectifier that costs around 100.00 is a much better power to dollar ratio than most other bolt ons.

[marty]

Hay DUNEITTILLUDIE do you feel it turn on and off, or does it know when your accelerating hard and shut the charging system down regardless of the batterys state of charge? Does it charge any better? It's cool to here from someone who has this thing. I too don't think pipes are the best investment. Several hundred dollars for maby 2 peak hp. and a shorter torque curve. There is better, cheaper ways to get more usable power. The loud pipes may just get annoyed nonatvers to call the cops or their congressman. On a street bike LOUD AND PROUD can save your life. On a quad it will just get us baned. Sorry for preaching J.M.O. Remember TORQUE MOVES MASS !

[marty]

I don't mean to beat a dead horse but I just looked at their ad again and thay never say thay shut the charging system off. Thay say "when the battery reaches 100% the system switches over to allow 100% of the spark from the charging system to go directly to the plug to create a hotter better burn that creates more horsepower."
First there is no "spark in the charging system". Second you cant send anything "directly to the plug" or even the coil without sending it through the C.D.I. Third these systems are separate. The C.D.I dose not get power from the same windings as the rest of the quad. If I had a scanner I'd post my wiring diagrams so wilkin250r could have a peek. Maby some one else can. I don't know where I'm going with this so lets go. I still say TORQUE MOVES MASS !

[TORO1968]

Originally posted by wilkin250r
Mechanical engineering requires lots of math.

I can vouch for that... :D

[plkmonster2]

Don't just unplug your regulator! I did that on my 200 3 wheeler. Fried the lights and battery!:eek2: