Rectifier Regulator Failure?

Slardy · Sep 21, 2012

OK fellows. Please put your thinking caps on and give me your opinions. Here is the situation.

2007 with 50,000 miles, electrical performance to that point was perfect with Datel readings of 14.1 to 14.2 volts @3-4k rpm and no extra load. The Datel is wired directly to the battery.

A couple of weeks ago, when returning from a 5 day trip, I noticed that the Datel was reading an unusually low voltage of ~ 13.1 volts, with nothing extra running. It was daytime. Based on what I remembered reading on this forum, I immediately suspected that my stator had failed. I had to travel another 200 miles to home so I began to nurse the 2007 home. As I proceeded, the voltage got lower and lower. When I got home, the voltage on the Datel was ~ 11.1 volts.

Again, because of what I had read, I ordered an OEM stator. Well, I removed the stator today and while the color had changed on the epoxy coating, there was no evidence of any failure! At this point, I decided to check the stator connector on the R/R: it looked perfect.

I put everything back together and checked the output voltage phase to phase. AT ~4000 rpm the voltage was steady and in the range of 75 to 80 volts. OK, you say, what is the problem? Buy a new R/R and get on with it. Well , I happened to notice that during all the handling of the stator as it was hanging from the wires to the R/R, I had managed to put a small chip on one of the coil frame bottoms. The chip is about 1/8 inch long and less than 1/16 inch wide, but enough to see the shiny metal frame at the bottom of one of the coils.

At this point, I plan to epoxy that chip and return the stator to service. What do you all think? Any suggestions on the type of epoxy?

I now plan to order a new R/R. But, have any of you heard of an R/R fail in the manner that I described? I would expect a solid state device to fail quickly without a lingering, declining voltage profile. What are your thoughts on this?

One final thing. I have been running a headlight modulator ever since I owned the FJR. Do you think the modulator puts any extra stress on the R/R as it causes a modulation in the power draw?

Slardy

PS: about a month before the trip I installed a Shorai LFX18A1-BS12battery

exskibum · Sep 21, 2012

Dunno, but I'll piggyback with my related Gen.I problem. I started getting fluctuating voltages on Monday on my '05 w/52K miles, no electrical load abuse beyond maybe a dozen days heated jacket use in its lifetime. The initial fluctuations started during a ride (seeing 13.5 to 14.3V when it has always shown 14.3 to 14.7 up to Sunday returning from Ray's RTE). It had apparently failed to keep the battery charged at one point on Monday's ride, causing me to have to bump start it after a stop. Fired right up several times in the next couple days, but the voltages were fluctuating even worse at idle when warm -- jumping erratically between 13.3 and 15.1V. Just removed the RR and cleaned the contacts. Tomorrow, I'm going after any and all contacts and connectors that seem potentially troublesome. Hoping that is all it is.

dcarver · Sep 21, 2012

Looky here, but go to thread end for Reader Digest version unless you're into techie talk...

bramfrank · Sep 22, 2012

Doesn't ound like that is your issue . . . if your Datel is right then the regulator is bad if you don't have 14 volts on the disconnected output terminals, though the thread does link you to a site where you can get the upgraded replacement regulator for less $$$$.

If your meter is sick you might want to note that you are about due for a starter failure. The problem presents as though you have a bad battery, when hot, when you try to start the bike the voltage will drop to the point where often the clock will reset, the starter solenoid clicks and the engine doesn't turn over - a bump start gets things going.

Epoxy the stator coil - you can even get away without the epoxy, though if it was mine I'd mix up a batch and apply it.

RossKean · Sep 22, 2012

For epoxy, I would use JB Weld. Its pretty good for temperature and oil resistance.

As for your problem, I'm not sure whether you have done enough for a proper diagnosis (or whether you have done it and spared us the gory details). First of all, are all of your connections tight and clean - especially battery terminals? Has the function of the Datel been verified using a good DVM? Assuming the meter is OK, I would start with a thorough check of connectors and continuity before I decided to buy a new stator or regulator/rectifier.

Also, have you had the battery load tested? (Not sure how a load test would work with a lithium battery but for sure I would at least check out the system with a different battery.) The Shorai is new to your bike and, as always, the primary suspect with any issue is what you last ****** with!!

BTW - assuming the headlight modulator is not defective and sucking a bunch of excess current, it shouldn't hurt anything.

Ross