| Author | Message | ||
     Mark_weiss |
08 Ulysses Battery dies at 9 months. No warning. Turn key on, dim lighting, barely a click from the relay box, no fuel pump noise. Battery checks at 13.2 with key off, 3.4 with key on. Leave battery on smart charger for a few days and check again. Battery alone shows 13.4, attach a 15w bulb and battery drops to 4.5. OK, need a battery. Just for the heck of it, I borrow a battery from another bike and start the Uly. At idle, battery voltage is 12.6. At 4k rpm, voltage settles in at 16.15. Seems pretty high, no? Bring the revs up to 5k, voltage rises to 17. Voltage regulator? Mark SE AZ | ||
| Reepicheep |
Yes. Which is proabably what killed your first battery (overcharging it, and boiling out your electrolyte). (I added an overvoltage indicator to my grip thermostat circuit I am designing... thank you for confirming it was a useful excercise! I could have saved your battery.) | ||
| Hughlysses |
I concur. Bad battery & bad voltage regulator. Voltage shouldn't go much over 14V even at redline. Before you buy a new VR, it might be worth checking the ground connections on your bike to ensure that a bad ground someplace isn't causing the voltage regulator to get a false reading leading to overcharging. This is another good reason to have some sort of voltmeter mounted on your bike. | ||
| Reepicheep |
True! If the VR isn't grounded well, it can't work. | ||
| Mark_weiss |
Anyone know where the VR is grounded to the chassis? I'm finding ground through the wiring, but there could be some resistance that affects the VM when the bike is running. Mark SE AZ | ||
| Husky |
Mark, the 09 XB Electronics Diagnostics Manual says Ground # 2 for the Ulysses voltage regulator. #2 is also the ground point for the following: Battery, turn signals, flasher, fuel pump, clutch switch, power outlet, ignition relay, key switch relay, instrument cluster, tail light, and license plate light. Husky | ||
| Mark_weiss |
Thanks. I'll interpret that as the ring terminal that comes out of the harness near the fuse/relay box. Same frame point as the battery ground cable. Mark SE AZ | ||
| Mark_weiss |
Is there a bench test for the voltage regulator? I've made certain that the connection is as clean as possible. Still goes to 16 v at 4k rpm. | ||
| Reepicheep |
There might be something in the factory service manual. I can't think of an easy hack for testing it without risking smoking something... Your on the bike rig is probably your best test. Check for continuity to ground from somewhere else on the voltage regulator case, and check for continuity across the infamous 77 connector, and if you have it and are still seeing 16v, you have a bad voltage regulator. | ||
| Mark_weiss |
New VR is on the way from Bumpus. I'd like to go local, but my nearby formerly-a-Buell dealer is really no longer interested in me. Mark SE AZ | ||
| Mark_weiss |
New battery & new VR. Bike starts & runs. Charging voltage, with a fully charged, new, battery, peaks at 13.7v by a bit over 3k rpm. Advancing the rpm does not lead to any further increases in voltage. Mark SE AZ | ||
| Reepicheep |
Sounds right to me. Little doubt that is charging your battery. | ||
| Mark_weiss |
Does anything special need to be done to ground the CASE of the VR? Today, the Uly stopped charging. It would seem that the ground lead in the 77 connector (which is grounded in tandem with the battery ground lead) would be all the grounding that the VR needs, but I'm wondering if I should have scraped paint from the housing before mounting the bugger. I'm supposed to make the three hour ride back home on Friday. I'd like to be able to make it. Mark SE AZ |
