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Bike electrics
quadra - 27/2/06 at 01:52 PM

Sorry for my ignorance, but do bike engines have alternators, as I can't remember seeing one on a bike. If not then how do they generate electricity.

Mike


zxrlocost - 27/2/06 at 01:54 PM

its all built in


mookaloid - 27/2/06 at 01:55 PM

They generally have them - but are not so obviously bolted on like car ones. they can be built onto the end of the crank or sit on top of the gearbox area.

I'm not a bike engine expert though


smart51 - 27/2/06 at 02:10 PM

The R1 has a built in alternator. It puts out 3 phase AC which is fed into a separate rectifier / regulator with gives you your nice DC voltage.


RichieC - 27/2/06 at 02:34 PM

quote:
Originally posted by quadra
Sorry for my ignorance, but do bike engines have alternators, as I can't remember seeing one on a bike. If not then how do they generate electricity.

Mike

Yep, they do but its known as a Generator rather than Alternator. The side covers on the engine generally house the generator; the bits that always get scuffed if the bike is sent down the road.

This one from an R6 shows the internal stator windings of the AC gene.

[Edited on 27/2/06 by RichieC] Rescued attachment generator_inside.jpg
Rescued attachment generator_inside.jpg


Gav - 27/2/06 at 03:43 PM

Oh i know them well! I had to get my old KR-1S 250 2-stroke stator re-wound on quite a few occasions!


Bob C - 27/2/06 at 07:31 PM

Car alternators have their magnetic field controlled by a wee circuit & fed via sliprings to the rotor so the 3 phase output is just rectified & fed out to the battery. bike alternators use a permanent magnet to generate the magnetic field (this spins on the rotor - note this means the 3 phase voltage supplied by the generator is proportional to the engine revs) so it's mechanically simpler but the voltage control now has to be done by the rectifier/regulator. The controller is thus controlling ALL the power output from the generator (which is why car alternators don't do it this way) .
here endeth the first lesson. . . .
Bob


tks - 27/2/06 at 07:42 PM

i want the second lessons and alos the finals...

Can you??/

Tks


Bob C - 27/2/06 at 10:33 PM

Hi tks - the last line was a joke - it's what anglican clergymen always said after the first bible reading in a church service. If you've got any questions whack 'em on here & we'll all have a go at answering them!
cheers
Bob


quadra - 1/3/06 at 08:21 AM

Thanks for that, I am now fully educated in bike power generation.

Cheers Mike