Dang, that's something you don't see every day, A motorcycle with an actual alternator with brushes and everything. and I say alternator as it's also got a rectifier listed,,, In spite of the parts diagram calling it a generator.
A Generator is rather generic as something that generates electricity.....it comes from early days of electricity, and they had a commutator ("brushes and everything") to make Direct Current (DC)
After Nicolas Tesla proved that Alternating Current (AC) was more efficient for distribution at long distances, , The term ALTERNATOR was adopted (not DC).
Alternator DOES NOT use a commutator ('brushes and everything") and is what is used in cars and motorcycles since the late 50's and early 60's ...output is also in more than one phase, usually three....... The conversion to DC current is made by electronic rectifier (diodes), in general, outside the alternator.
Most old time mechanics will tell you that generators produce DC (Direct Current) while alternators produce AC (alternating current). Makes sense eh? This is because the old timers remember when all cars and trucks used generators and alternators were unheard of.
If you google it you will find that in 1960, Plymouth was the first car manufacturer to switch from using a generator to using an alternator. After that innovation, eventually everyone switched to using alternators but the term generator had been used for so long it refused to die and many refer to alternators as generators.
My KLR has no brushes, no commutator yet on the parts diagrams it refers to it as a generator but at least the service manual gets it right or perhaps I should say the manual gets it more correct. One can argue that anything that generates electricity of any kind, is in fact a generator like Hugojose said. It's just more precise or more accurate, if the device produces AC to refer to it as an alternator.
One interesting thing I learned just now is that some alternators can use carbon brushes!
These are referred to as Lundahl or 'claw-pole' field construction alternators. Learn something new every day!
In general for most people who do not troubleshoot an electrical generating system, it does not matter what you call it.
However for those doing their own electrical troubleshooting is important to know the differences. As the term 'Generator' does not specify what kind it is, and even suggest DC from the early days with mechanical commutators.... I've heard people even calling it the 'stator', but the stator is only the non-moving part of the alternator. The other part is the rotor(magnet) that moves, and on motorcycles with the ALTERNATOR on the crank, it also serves as mechanical flywheel to smooth out the crank..
In general, in modern motorcycles, what we have is an ALTERNATOR, and the three yellow wires (Kawasaki) are alternating current in three phases 120 degrees apart from each other, depending on the bike, the peak voltage may be as high as 80 volts (AC) and the instrument has to be set on AC to read it. ..
The Rectifier/Regulator takes the three phases and converts it to DC electronically, solid state, no moving parts, no wear........ and the regulator does its darnest to keep it around 14 VDC.....and to read this the instrument has to be set to DC.
........only part I can think of uses a commutator on the bike (brushes and everything) is the cranking motor.
Great discussion, perhaps a bit anal , but yeah I pretty much agree with all points made. Having "grown up" in the US Navy Nuclear Power program on a submarine and doing industrial maintenance as a 40+ yr career I agree with the idea that "everything has a name" *. Use it. And when conversing with non-tech people I all too often leave my Dumbazz Translator at home and annoy the crap out of everyone by asking questions to attempt to define the problem.
Anywho, to the original question- where is the d**n thing on this motorcycle ?
* The actual quote I've always remembered is from a book I read circa 1983 called The Lords of Discipline by Pat Conroy. It is as I recall, "Do everything well and leave nothing to chance. There is no such thing as an insignificant detail and everything has a name." That's stuck with me throughout my entire career.
In addition to the old school actual generator, there are actually two types of alternators (that are typical in auto/bike use).
The common type in autos has a field winding on the rotor (powered through a pair of brushes) to generate the magnetic field and the actual power generating 3 phase power generating winding on the stator, with the diode array on the back. Early ones used separate regulator, later ones used an internal regulator ('1 wire' alternators), and some of the latest cars have gone back to external regulation and actually use the car's computer to serve as regulator in addition to door locks, a/c, etc).
Most (obviously not all) bikes use what's also known as a 'dynamo' or permanent magnet alternator. Instead of a field winding to make the magnetic field, it uses an array of permanent magnets. It rarely has the diode array internally mounted; they're typically in the regulator itself. Two types of regulators; early ones were 'shunt regulators' sending unneeded current to ground to keep voltage stable, generating lots of heat. The newer type basically lets the AC voltage from the alternator go as high as it wants, but has a high frequency 'switcher' that sends varying length pulses of DC through a filtered network to maintain voltage. Dynamo advantages: very compact, light weight. Disadvantages: no/poor output at low rpm, AC output voltage/current continues to rise with RPM (higher RPM=more energy, since magnetic field strength is fixed), somewhat more limited in total current output due to non-varying magnetic field strength. Most powerful one I've seen for bike/tractor/etc use is around 30A, while automotive style alternators can go well above 100A. I suppose there's no theoretical limit to output from either style; just talking about what's typically available.
I don't know where it is on that particular bike, but the 1st place I'd look is the end of the crankshaft on the side of the case where the wires are coming out of the case.
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