Motoplat alternator: 3-phase or single phase?

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noish
Cucciolo - the Lil Pup
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Motoplat alternator: 3-phase or single phase?

Post by noish »

After a several year hiatus, I've decided to have another go at getting the Ugly Duc (77 500GTL) running. I need a regulator/rectifier for it and was wondering if the Motoplat alternator is 3-phase or single phase? The stator has 3 wires (two yellow, one red) and 6 coils. What aftermarket brands are recommended?

tim
esa
Cucciolo - the Lil Pup
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Post by esa »

Hi,

I don`t know what R/R is recommended but I used one from Honda CX 500. I can post connecting instructions if you need.

Esa
Esa
noish
Cucciolo - the Lil Pup
Posts: 19
Joined: Mon Jan 17, 2005 5:50 pm
Location: San Diego

honda cx500 RR

Post by noish »

would you mind posting instructions? If it works on your bike I'll order an aftermarket honda cx500 regulator/rectifier and follow your instructions.

tim[/i]
esa
Cucciolo - the Lil Pup
Posts: 14
Joined: Thu Sep 23, 2004 12:36 pm
Location: Finland

Post by esa »

I`ve been using CX`s R/R for couple of years and it works.
When using electric starter and lights in city traffic the battery needs to be re-charged time after time, but I quess this is because of insufficient output of alternator.


Here are the instructions, this was copied from same net forum:


"
The black wire(s) are NOT ground wires. The black wires must be connected to a SWITCHED POSITIVE 12 volt wire. I added a pigtail "T" to the wire that runs the tail light (not the brake light). You can tap into any wire that's live when the key is on. These are the "sense" wires that the regulator uses to sense and adjust its output. Do NOT just hook these into the red wires.

The GREEN wires are the ground wires. Kinda like house wiring. Make sure these have a good connection to battery ground.

The RED wires are battery +12V. If you don't hook these into the red+12V wire on your bike, make sure there's still a fuse in the circuit. In other words, if you connect it directly to the battery, you'll need to add a fuse.

The yellow wires hook into the stator wires in any order. One leg of the stator wiring usually is routed up to the headlight for no good reason, so many of us have bypassed this loop of extra wiring.

The way I understand it, the duplicate wires can be hooked together -- they're just Honda's extra insurance against bad connections.
__________________

3 yellow => 3 stator wires (any order)
Green => ground
Red => battery positive (through fuse)
Black => SWITCHED positive (any +12v circuit that's only live when the key is on). You'll need to add a pigtail or T connection.


In my opinion any 4,5 or 6 wire R/R from a larger cc motorcycle will work as long as it has 3 input wires from the stator.
the 4 wire has 3 inputs from the stator + one output to the battery and it is grounded through the case of the R/R.
the 5 wire R/R is the same as the 4 BUT has an additional ground wire that is connected to the frame or the negative battery cable.
the 6 wire has in addition to the 5 wire has a sixth wire that must be connected to a wire that is hot with the key on.
I like the Shindengen brand R/R such as the sh-232 from a honda.
"
Esa
noish
Cucciolo - the Lil Pup
Posts: 19
Joined: Mon Jan 17, 2005 5:50 pm
Location: San Diego

more RR problems...

Post by noish »

So I purchased a honda 3-wire RR and connected it like this:
Green to ground
red to 12V+ end of the battery through a fuse
black to a circuit that's switched on only when the bike is on
3 yellows to the three stator wires

I always keep the battery on a trickle charger, and I noticed that after I installed the RR, it never seemed to finish charging. My multimeter tells me that the red RR wire that is attached to the positive terminal is leaking off about 2.5V of current when the bike is off. Do I have this installed wrong? Or is my RR bad?

tim
esa
Cucciolo - the Lil Pup
Posts: 14
Joined: Thu Sep 23, 2004 12:36 pm
Location: Finland

Post by esa »

I hope you got the pm I send you some time ago.
Did you cut off the red wire going from Duc R/R to fuse?
Esa
nottonight68
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Post by nottonight68 »

just saw this post-did you sort your electrical problem
noish
Cucciolo - the Lil Pup
Posts: 19
Joined: Mon Jan 17, 2005 5:50 pm
Location: San Diego

Post by noish »

funny enough - the honda RR worked great - it was the starter solenoid that was leaking current and I figured this out when I was trying to start the bike at night and noticed all the sparks shooting out of it....

Unfortunately I've been through the wiring so much that at this point it doesn't resemble the wiring diagram at all. But it work fine. Thanks for all the help.

tim
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