Testing a voltage regulator/rectifier M900 1997

[beastie]

I think my regulator is going bad. Is this a common thing for Ducs?

My initial tests were: I checked the battery voltage w/ a voltmeter when the bike is idling and reads 11.30 to 11.75. Even when revved up it doesn't even hit 12 volts, it goes up a little like 11.75~11.85.

Now how can I test the regulator itself to make sure its bad before spending the loot? I got the yellow/green/gray wires if I recall correctly.

Pretty sure its going bad, just wanted to be extra sure!!

Thanks again guys

[Howie]

You would check voltage coming out of the stator.  Disconnect the connector that joins the stator and regulator.  You want to see about 30 volts at 2K RPM and 90 at 6K RPM and voltage from each wire should be within about 10%.  Now you know the alternator is working.  Don't condemn the regulator yet, though.  Look at the connector you just disconnected.  If it looks burnt this could be your problem.  There is also a  separate fuse for the regulator by the right side of the battery under a cover.  if this fuse is blown you will not charge.

Tons of generic info here:


If you do need a regulator you can buy one made by Electrex from or friends at California cycleworks.
http://www.ca-cycleworks.com