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Discussion Starter #1
greetings
i got the red light on my 98 st2. i did the search on stator testing and found the following.
1 unplug the rr
2 test the 2 yellow leads from the stator are not open to ground. R should = 1 ohm and inspect the condition of the yellow wires.
3 start the bike, @2500 rpm each yellow lead from the stator should show 30VAC.
4 plug the rr back in, @ 2500 RPM, should show 14 VDC at the battery, plus check the rr fuse on the side of the battery box.
does that pretty much cover it except for the $ to cover the parts!
 

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The AC voltage coming out of the stator seems a little low, but that maybe OK at 2500 rpm. Does the voltage increase if reved to 3,000 to 4,000 rpms?

What DC voltage do you have across the battery terminals?
Ignition on, not running:
After start, Idling:
At 3,000 rpm:
 

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Discussion Starter #3 (Edited)
those weren't my actual nunbers, i lifted them from a search on stators. here's my actual at the battery. i had to run out for a new multimeter as the old one died.
ign off 12.98 VDC [just of battery tender]
idle12.32 to 12.39 VDC
@ 3000 rpm 14.24 VDC

i just recently relocated the rr to the desmotimes aluminum bracket, cleaned up the dried material on the back of the rr and applied new paste, did all the plugs to. ran fine for a few hundred miles, the battery light flashed a few times, now it is on full time.
 

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The voltages at the terminals seem good. If you ride around for 30 minutes, shut of the bike, will it start up easily or does it turn over slowly? How old is the battery? Is it the orginal R/R?

You could also measure battery voltage across the terminals at idle with everything on, high beam, brake light, turnsignal then hit the horn.... see what draws the most voltage.
 

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Discussion Starter #5
its the orginal rr but the bike has little over 4200 miles. it seems to have sat 2003 to 2008 when the 2nd owner picked it up and put a few hundred miles on it between sept 08 and june 09 when i purchased it. i put 6 miles on the bike from the time i whitnessed the red light come on, thats maybe 15 or 20 min riding on back streets. guess i will try riding it around for 1/2 hr and see what happens.
 

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Your post is a little confusing. Sounds like you relocated the RR before the red light came on, and NOW it's on?

The logic for troubleshooting is GREAT, though! Need decent AC voltage on yellow wires, then the RR takes it from there.

There's a chance that the red light is on as a malfunction of the RR, verify the reved voltage at the battery. 14.5V was typical on my 1998 ST2 (2500rpm, and after about a minute or 2 of charging).

A flicker of the red light right after startup would point me to the large black connector on the yellow wires. I found mine fried after noticing this light (the light would go out on mine after I blipped the throttle once).
 

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Discussion Starter #8
i doubt the battery is original. i did see the light come on for around 10 miles on the 80 mile trip home when i purchased the bike. it came on a serveral times after i relocated the vr, but just briefly. i have gone through all the connectors, wires and added the paste to the connectors. the bike sat in my garage for a few weeks while i was awaiting parts, especially the belts. the orginal belts looked ok when i replaced them. i think i will just install a desmotimes voltmeter, black out the light and call it fixed. thanks for all the sage advise.
 
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