Leg burned by alternator???

[Tucson_Guy]

I was riding my 1982 CBX last week and hadn't gone far when my left leg began to feel like it was on fire. I couldn't stop so I continued to ride the bike for a while. My leg felt like it was on fire the entire time. I never felt anything like that before. I got to my destination and rested for a while. When I drove my bike back home, I experienced the same thing. It was dark when I got home. When I checked my leg it looked like it was severly burned, but not like an exhaust pipe burn. There were no blisters. It was like it had been baked. Is it possible that the alternator got so hot for some reason that it actually burned my leg even through my pants? The only thing that looks like it could have been close to the burn area is the alternator. I would be interested in your opinions. The alternator seemed to be working ok although it was showing a very high rate of charge. I won't be able to ride the bike again for weeks. I need to figure out what would cause such a thing to happen. Thanks for any ideas.

[EMS]

Welcome, Tucson_Guy!

Maybe the bearing in the cover is starting to fail and generates the heat...

[NobleHops]

Yeah, I thought about that. That sucks. It's three bolts to get that cover off, and if it WAS the bearing and it was throwing that much heat, it'd be pretty toasty-looking in there I imagine. All those bearings and seals are probably toast even if they were NOT the real cause of the heat though. Look up threads on servicing the alternator to see, but I personally doubt that the bearing going south could generate that much heat by itself. I'm more curious about the state of your charging system, given the high charge rate you report. Maybe the regulator/rectifier is going? Or there is a bad winding and a lot of resistance in the alternator? Or a bad connection to the wiring harness or ground that is putting a lot of resistance in the wires? In any event, search the threads here and find your way to Mike Nixon's website at http://www.motorcycleproject.com and read his tutorial on troubleshooting the charging system.

CBX-tras sells modern alternator conversions for somewhere around $600, and they are very highly regarded. But don't slap one on till you know what's going on.

N.

[Larry Zimmer]

I would completely concur with Nils.

[daves79x]

Can't imagine how you are sitting on the bike for the alternator to actually burn your leg. Bad bearing or no, the alternator gets to engine temperature which is clearly hot enough to burn you, just can't imagine how you are sitting for this to happen. Generally the CBX is not a 'hot' bike to ride. Much cooler than some of it's modern water-cooled counterparts. And I've ridden my CBX in Tuscon in the middle of the summer.

Dave

[Dave Ditner]

I'd bet rectifier/regulator. You said it was charging a lot. If I remember right it's rated at 360 watts. At 14 volts that should give you about 25 amps WFO. With a decent battery and no system shorts, it wouldn't do that very long if the regulator were any good. It would charge the battery then back off on it's output and the battery voltage came up.