Join Date: Jun 2018
Location: Northern Ontario Canada
Sudden no start, dead battery
Want to share a story with you guys.
Went for a short ride with a buddy this week. Stopped the bike just a few hundred feet from my home. Came to start the bike back up. Wouldn't start! Nothing but relay buzz. Battery had mistiriously just died. My buddy towed me the short distance home. Get home check the battery posts, they were on solid. Check the battery with my multimeter, only showing 11.5 volts. Boost the bike with another battery, bike starts right up. Let it run with the booster battery for a minute, then disconnected it. While the bike still running I checked for voltage across my bike's battery posts. Only showing 12.3v instead of 14+ volts! Obviously the charging system isn't working. Couldn't do much more as I had to go in for a nightshift. Next day I checked all my fuses. They were good. Start looking threw my Yamaha service manual on my phone. Read the troubleshooting guides and electrical schematic for my bikes charging system. Found the voltage regulator / rectifier. Unplugged the red and black wire plug that leads to the ground and battery.
Ground tests good , and I get 12.5v battery voltage from the red wire. Motor to ground checks good as well. Unplugged the 3 white wire stator plug form the voltage regulator. Check ohms across all three stator phase wires. On spec for my 09 Grizzly is 0.108 to 0.132 ohms. I'm showing 0.4 ohms. Out of spec! Borrowed my dad's multimeter, same thing. Did some more research. Learned two other stator testing methods on YouTube. One is to check for continuity from each phase to ground. Yup all three are grounded witch is obviously bad. Start the bike check for voltage between all three phase. Should be about 20 volts on idle. Nothing, zero voltage. My stator completely fried!
New stator and gaskets on order. I have a big 6 day riding adventure coming up in less then a month, I can believe this failure happened so close to home and just in time so I could diagnos and solve the problem! Got lucky in my misfortune.
2009 Grizzly 550 Special Edition, Red Midnight Armour, EPS, 26"Pitbull Growler BG2.5 xor, on 12"polished alloy SE wheels with 1"spacers, Yamaha overfenders & windshield, Heat Demon grips & thumb warmers, 2500lbs Warn winch, two up seat / storage box, Moose rear bumper, Gold Plugs in diffs & engine, COOP45 machined sheave + 0.5mm shim (3.1:1), 18 gram weights, EPI Orange spring
Last edited by Vincent; 04-27-2019 at 08:15 AM.