GT550 Rectifier, Regulator Failer?

[Adam M]

I was riding my gt550 last week when all of a sudden the lights dimmed and the blinkers stopped blinking. I pulled up to a stop sign and the bike stalled. The lights would still turn on, but were extremely dim. No matter how many times I tried to kick it the bike would not start. Towards the end of my long push home, as I was rolling down a hill, i thought I'd try to pop it into gear. The bike started and i rode the rest of the way home. It will run for about 5 minutes, before a nasty plastic-y smell starts up from under the left side panel and the lights dim and bike stalls. It will only start again after having sat for a while.

I might add that i put about 120 miles on the bike over the previous weekend, and this had no positive effect on the life of my battery, which is perpetually dead. I haven't been able to push button start the bike since over the summer.

I don't really know anything about electrical and any help would be appreciated. Especially because this is my only transportation. Thanks, Adam

[jabcb]

The "plastic-y smell" could be coming from an electrical short.

Looking over the wiring & electrical components for burn marks. Also look for damaged wire insulation, broken or nearly broken wires, and loose connectors. You might be able to smell where the problem is.

The electric start probably doesn't work because the battery isn't charged up enough to spin the starter motor.

If the battery has water level markings, make sure it has enough water. Top it off with distilled water if needed to bring it up to the lower water level marking.

You should charge up the battery. Use a low output charger and don't leave it on too long.

Do you have a multimeter or have access to one?

[Adam M]

Thanks for the reply.

I do have a multimeter. I used it to do some testing. On the rectifier, I tested the resistance between the yellow leads and red lead in both directions and i now believe that those connections are good. The clymer manual i have tells me to test resistance between the yellow leads and a black lead, but there is no black lead to be found. Atleast as far as i can find.

On the regulator I check for continuity between green and black/white. As well as green and orange. Both seemed ok. Although i got a beep out of the green to orange test, and only a meter reading when i checked the green and black/white. I did not open the regulator cover to test for resistance between orange and green.

and I also tried to get a reading of dc voltage between the battery terminals at 3000 rpms. I didn't get any conclusive results from this test, because i don't really know what i'm doing with the multimeter. Slash i think i must have either fried it, or the battery coincidentally died.

I checked the battery acid and all the levels are good. The battery is only about 1 and a half years old.

I noticed a dramatic change in the brightness of neutral light when i switch the run switch from off to on.
Also the bike always seems to stall immediately when i turn the blinker on.

I will do some investigating tonight to see if i can find any wires that look suspect. Thanks again for the help

[r3tro74]

Also the bike always seems to stall immediately when i turn the blinker on.

Just use hand signals instead of the blinker.

[jabcb]

What kind & model of multimeter do you have? Is it autoranging or do you have to set the voltage & resistance range? (Useful to provide a pic if you aren't sure.)

Did you charge up the battery?

[Adam M]

It was a 17-range analog multimeter. You did have to set the range on it, until i blew it up or something. Is this possible? it worked fine yesterday and now it doesn't work at all. I assumed the DCV setting, which has 10, 25, 50, 250, and 500 settings, functioned as a dc voltmeter.
I'm gonna try new batteries tonight, but it smells broken.

I have not charged up the battery yet, because i don't have a trickle charger. I have to borrow one from my friend, as I'm currently too poor to buy one.

I have not been able to track down any burning wires, but i definitely noticed that the rectifier was somewhat warm to the touch after about 5 minutes of running. However i don't know whether or not that is normal.

I have been using hand signals, but my bike has about a mile and a half range before it just stalls out anyways.

[jabcb]

The multimeter might have a fuse & it could be just a blown fuse. Also could have the test leads in the wrong jack. (You wouldn't be the first person to do that.)

If its a trickle charger don't charge the battery for more than a couple hours. If its a battery tender or battery maintainer you can charge it up as long as you want.

The rectifier normally does get a little warm, which is the reason it has a lot of metal surface area. Modern rectifiers don't produce as much head & are a lot smaller.

[Adam M]

Obviously charging my battery is something that I need to do, but are you suggesting that doing so could eliminate my problem? Or do you think it goes beyond that? I don't think that the burning smell is coming from the battery, although i have not pinpointed it yet. Thanks again for all the help.

[jabcb]

Two reasons for charging up the battery.
Electrical problems & deep cycling can shorten battery life considerably.
When testing the electrical system its easier to make sense of the results if you start with a fully charged battery.

[ctluba]

Hey Adam,

You ever figure this out. I am having the EXACT same issue, neutral light dims when switch is thrown to "run" position. Cant find any short anywhere. Gonna spend the day tomorrow and I better get this straightened out!!!!!!!!

[tz375]

On one of my bikes, I have a similar situation. The battery is new AGM but it's really too small and it doesn't hold a lot of charge for very long. Once the bike fires up, it charges OK.

So in my case it's a battery that's too small. Yours could just be a dead battery. Start with a well charged battery - borrow one if needs be and go from there.