charging system went poof

I was riding down the highway at about 40mph when I heard something pop and a puff of grey smoke came up from the under the plastic near the triple clamp. The engine died and I coasted off the road. After sitting for a minute, I hit the starter button and it started right up, so I continued down the road since I was in a very rural area. About a mile or two down the road, another puff of smoke and the smell of burnt rubber, this time the bike kept running but the battery light was on (may have been on the first time but didn't notice it). At that point I knew the battery wasn't charging and kept riding to get to the nearest city, at the top of the exit ramp the bike died and no more battery.

I can't see any burnt wires, fusable links, blown fuses, etc so I am guessing the alternator died...? I charged up the battery and put a VOM over the terminals with the bike running, and its showing 12.25v - nowhere near the 14+ I would expect from a properly working charging system.

Anyone have this experience? I just want to make sure I don't overlook anything before replacing the alternator.

Thanks,

Bill

I was riding down the highway at about 40mph when I heard something pop and a puff of grey smoke came up from the under the plastic near the triple clamp. The engine died and I coasted off the road. After sitting for a minute, I hit the starter button and it started right up, so I continued down the road since I was in a very rural area. About a mile or two down the road, another puff of smoke and the smell of burnt rubber, this time the bike kept running but the battery light was on (may have been on the first time but didn't notice it). At that point I knew the battery wasn't charging and kept riding to get to the nearest city, at the top of the exit ramp the bike died and no more battery.

 

I can't see any burnt wires, fusable links, blown fuses, etc so I am guessing the alternator died...? I charged up the battery and put a VOM over the terminals with the bike running, and its showing 12.25v - nowhere near the 14+ I would expect from a properly working charging system.

 

Anyone have this experience? I just want to make sure I don't overlook anything before replacing the alternator.

 

Thanks,

Bill

Afternoon Bill

It sounds like maybe the alternator belt shredded or failed. Worth a look anyhow.

If it is a failed belt then possibly the alternator locked up to cause it so check for that also.

If the belt & alternator are still good then look for burnt wiring or ??????

Much more likely that the belt gave way than the alternator died. If you determine it was the belt look carefully for belt fibers drawn into the alternator and around the pulleys and shafts.

Again, assuming it was the belt, you will also want to check to be sure that the alternator shaft/pulley have not been damaged and are running true. This may be a bit hard to tell with a simple visual inspection on a non-running bike, but any damage will be obvious when the belt is in place and the bike is running. Any wobble at all will be a concern.

If in fact the alternator belt has shredded, when you replace it, do not over tighten it (8 Nm is spec). My over tightened belt shredded, wrapped around the bottom pulley, killed the sensors and toasted the motronic. I had just had the HES rewired in Canada and re-assembled everything but had too much tension on the ribbed belt and it separated and flew apart. 'Twas an expensive repair, just for the parts. I supplied the labor.

Alternator belt makes a lot of sense, that would explain the burning rubber smell. Plus, I found a couple of small hair like metal fibers laying in the area under the alternator.