Help with wiring Reg/Rec

[falcon]

I am wiring in a regulator/rec from a new bike into my 1970 T250. I just need some clarification regarding wiring. It seems as though the stator is 4 phase, or one of the wires is split into two? I have the two points wires coming from that area, a ground wire and then four other wires, all of which have continuity between each other and none of which ground. From looking at the wiring diagram, it seems like one of the stator wires goes directly from the stator to the ignition switch? Would I do the same with wiring in this new style reg/reg, or should I splice two of them together since my reg/rec only has 3 stator wire inputs?

[tz375]

AFAIK, there should be one common connection that goes to one side of the rectifier Y/G. G/W and G join each other and go to the light switch and from there it goes back to join one other wire R/G to bring that extra set of coils on stream when the lights are on. A third goes to the rectifier and regulator (R/G) that's the one the switched coils connect to.

So R/G to R/R
G + G/W to light switch and join R/G at R/R
G/Y common connection across all alternator pairs of coils to R/R

[jabcb]

What regulator/rectifier do you have?
If it has 3 yellow wires for connecting to the stator, then you have the wrong type of regulator rectifier.

The regulator/rectifier should have 2 yellow wires.
You can wire it up 2 different ways. Either for full output all the time, or to switch on the lighting coil when the lights are on.

Diagrams for the GT500 show the two different ways to wire it up.
Note: stock the GT500 has a voltage regulator & your T250 doesn't.
viewtopic.php?f=29&t=5963&hilit=gt500+r ... r&start=30

[falcon]

Ok, sounds like I have the wrong one then. So green/green together and to igntion? Ign IN 12v or 12v out? I have a 35amp bridge rectifier kicking around, that should work yes? Wire up, ground/12v and two AC in? Is it useless to get a regulator on this small bike? Am I making more work for myself than is needed?

[falcon]

My low beam will be wiried in to be on all the time (local regulations), so if I wire it to run full output all the time with only a small bridge rec., will it be OK? Anyone know how many AMPS the stator pushes on these little motors?

As I don't have CDI, what do I do with the other green wire? I noticed the P/O who did some odd wiring in this bike had the green and green/w stripe wires connected together and both to the ignition switch.

[jabcb]

For T250/T350 alternator specs, see page 17 of: http://www.ozebook.com/compendium/suzi/suzidata1.htm

Page 17 also has a diagram of how your alternator & rectifier are wired up.
Stock, the alternator G wire is connected to the G/W wire.
Connecting the alternator G wire to the R/G wire increases output with the lights off.

The T250 uses the battery as the voltage regulator. At high rpms the voltage is too high by modern standards but its ok for the T250. But it shortens light bulb life a bit.

If you have a conventional battery then you don't need a voltage regulator. Just make sure to top off the battery with distilled water occasionally, and make sure the battery overflow tube is properly connected.

If you have a modern maintenance free battery, then you should add a voltage regulator. Otherwise the high rpm voltage will exceed the battery's voltage range specs.

In my state, the local regulations also require daytime headlight use. But the law only applies to bikes made after a certain year. I've forgotten which year, but if the bike is designed to allow you to ride with the headlights off, then its ok to do so.

A bridge rectifier like the ones from Oregon Motorcycle will work fine.
http://www.oregonmotorcycleparts.com/rectifiers.html

If you wire up the headlight to be on all the time, then you should do the same with the alternator lighting coil.
In the next few days I'll draw up a diagram to show how to wire it up.

[jabcb]

Stock wiring for the T250 alternator.

T250_alternator_stock.jpg

Recommended change to increase output when lights are off. (see different connection for alternator G wire)

T250_alternator_std_mod.jpg

Wiring change when lights are wired up to be on all the time.
Also provides maximum output when you replace rectifier with regulator/rectifier.

T250_alternator_max_output.jpg

[falcon]

Awesome! Thanks for the diagrams I will get to work and report back.

[joethebike]

Thanks for your old post jabcd as I had battery boiling issues with my T350 and your clear wiring diagram prompted me to try the Tympanium regulator/rectifier with complete success. A stable battery voltage of 14V with the engine running means my new sealed battery should have a long life.