Yet another charging question (yes, another stator issue!)

[Sabre]

OK, I've read all existing threads with interest, and have a great THANK YOU to express for all those who've shared their knowledge and experience. My '05 has been requiring occasional top-offs of the battery for some time. Replaced it two years ago. No real failures, just gets tired on occasion.

She recently let me down suddenly. Limped home, recharged the battery, and first fitted a Datel voltmeter so that I could learn something about this whole problem. Oh yeah, the Datel is wired via relay directly to the battery with 10-guage wires, soldered connections...should be minimal line loss there. Here are the signs and symptoms:

1) Volts at idle: 13.3 vdc
2) Volts at 2500 rpm: 12.5 vdc. More revs do not change voltage.
3) Impedence of stator wires (A-B, A-C, B-C) is zero ohms, not infinity. All pairs appear to have perfect conductance. I thought they're supposed to be infinity. (Measured with key off)
4) Stator voltage at 4,000 rpm: 65 vac for all three pairs.

I'm hopelessly confused. I read the thread about the guy's wattage dropping off when the beast is hot. This bike is cold for all measurements. If someone can help me understand this, I'd surely be grateful!

I have the Sasquatch fix ready to go, including the Maxi fuse, but I want to understand this failure in the OEM configuration before I start "fixing" anything! Thanks in advance!

[Stretch]

As you read this thread...

http://tigertriple.com/forum/index.php/topic,5163

... you'll find that German's bike showed similar symptoms to yours, and in the end his trouble came from the Charging System Fuse (fuse #2 in the underseat fusebox) overheating its connectors, and melting that portion of the fusebox.

Maybe that's all it is, and a Sasquatch Fix (bypassing the fusebox) will fix you right up.

Also in this thread, you can read about my charging system troubles, which left me stranded a few hundred miles from home.

If you do decide to replace your Stator or Regulator / Rectifier, you'll also read of my recommendation to replace both parts at the same time, to avoid see-sawing back and forth... one bad part frying the other, and back-and-forth ad nauseam.

Impedence of stator wires (A-B, A-C, B-C) is zero ohms, not infinity. All pairs appear to have perfect conductance. I thought they're supposed to be infinity. (Measured with key off)

You're good.  There's supposed to be continuity (close to zero Ohms) between each of the three Stator wires, and Infinite resistance between any Stator wire and Ground.  If you have continutiy between a Stator wire and Ground, your Stator has an internal short to Ground, and must be replaced (along with the R/R, since the dead Stator may have fried it).

[Sabre]

Thanks for your detailed reply, Stretch. OK, ran out to the garage, and re-read that thread, too. Here's what I see:

1) yes, zero ohms resistance across three stator pairs is good;
2) there is indeed infinity resistance between each stator wire and earth
3) the 30-amp charging fuse (#2) is fine, the socket is fine, and the entire fuse box is fine.

So it seems like the stator is good and the fuse is good. Could this now be an isolated R/R failure?

[Stretch]

That's what mine was, a R/R failure.  Not surprising, considering the stock SCR-type Regulator Rectifiers generate a good deal of heat on their own.  Couple this with the fact that Triumph, in their infinite wisdom, chose to mount this heat-generating device, which must be kept cool, in one of the worst places on the whole bike... tucked into a tightly-enclosed space with the only airflow coming from the back of the engine... very warm air.

That's why I swapped my R/R for a MOSFET-type unit, and mounted it on the outside of the bike.  After running for hours, the new R/R is scarcely warm... the bodywork is hotter from being in the sun.

http://tigertriple.com/forum/index.php/topic,6180