gt185 Charging Problem

haasdaddy · Posted: Thu Jun 02, 2011 2:03 pm Post subject: gt185 Charging Problem

I have a 75 gt185 and it is not charging when I ride it for a while the battery dies and so does the bike also while it is running I can pull the neg off and it dies. Any help on what I need to change on it would help.
thanks

MR.CHocko · Posted: Thu Jun 02, 2011 3:02 pm Post subject:

There are two things you are going to need to check. First I would suggest that you go and get a multimeter. You should be able to get one at Walmart or at any autoparts store. Next there are two things that could be causing your problem. One is your rectifer and the other is your stator. I am not sure if you know how to test either one, but I am sure there are some people here who can probably describe the procedure better then I can.

Rizingson · Posted: Thu Jun 02, 2011 7:26 pm Post subject:

That bike will always die if you remove the battery from it's circuit.
The Gt185 has an old school type of charging/starter setup. It uses a generator (starter dynamo) and to control charging voltage it has an old style voltage regulator consisting of a cutout relay to control output. (no diodes or rectifier due to the use of a commutator)

Some problems with this system that causes poor or no charging are:
1. burned up contacts in the voltage relay (replace relay).
2. Dirty commutator surface (can be polished with 400 grit wet paper).
3. Grounded armature coil (checked for conductivity between commutator surfaces and core. If conductivity is found, replace the complete armature.)
4. Failure of carbon brushes. (replace if shorter than 14mm)
5. Damage in field coil of generator. Check the starter field coil terminal,(yellow wire) and red w/green trace wire and the dynamo field coil (green wire) and the red w/ green trace wire for conductivity. If none the wiring is damaged.
6. Grounded out coils or Internal wiring. Check the Red w/green trace and ground circuit. If it is conductive than the field coil or dynamo coil is grounded.

To check the voltage regulator, first disconnect the red wire from the regulator to the battery and take reading from red wire to ground. It should read a no load voltage between 15.4 to 16.6V above 3000 rpm. If it reads more than 16.6 or no volts regulator may be bad or its contact points burnt.

Hope this doesn't sound too difficult, I'm not sure how to put it in more simple terms. I realize the technology used here was abandoned in the automotive field around about 1960. So if you don't understand the terminology you can always look it up online.

haasdaddy · Posted: Sat Jun 04, 2011 7:24 am Post subject:

thanks a lot i will try that this weekend I am really thinking that it is my stator I just what to narrow it down because on a tight budget I can't buy a bunch of unneeded parts.

haasdaddy · Posted: Thu Jun 16, 2011 8:09 pm Post subject:

I think I found the issue one of my brushes was broke off completely.