electic gremlin

[KARSTEN]

I have corrected most of the issues,actually all,that are of mechanical nature on my (still new to me) 1985 R 80RT.Bike has 29K on it and I replaced all fluids,cables,cleaned and synced the carbs,replaced the roller bearings,set timing etc.Thanks to all that helped me along with advise.
I am faced now with an electrical problem,happened three times in a week.Same circumstances every time:I let of the gas,begin to apply brakes,turn turnsignal on and there it goes:The voltmeter goes nuts, the indicator needle makes wild swings ,the alt. light stays on for a few seconds and after a few seconds all returns to normal.I can not replicate at will but as I said earlier it has happened several times before.Any suggestions on where to look for the gremlin?I also have a question regarding a small rectangular plastic "box" about 1x3/4 inch.mounted to the frame under the tank,closest to the seat on the right hand side,the removable lid has 3 compartments,the box itself has 6 holes, in five of them there is a wire one of which keeps sliding(falling) out and nothing in # 6 opening .I have looked in the clymer for clues but can not identify.Hope to straighten this out,planning my first day trip from Mobile to the south of New Orleans this wednesday,this will give me a round trip of about 450 miles.

[Bill Burke]

Find all fuses in the bike, remove them, clean the ends and their holders, apply dielectric grease to the fuse ends, place the fuses back in their assigned holders and see if your odd electrical behavior goes away. Can't help you on the odd box issue.....an R80RT guy should have your answer there.

[shire2000]

Go thru that bike and check evey ground wire you can find. I bet you will find one is loose or has some major corrosion on it. Clean them all and make sure they are tight. It is amazing the problems that a bad ground can cause.

[jforgo]

Check diode board and all connections. Chuck it if any sign of overheating.

[squiffynimrod]

I also have a question regarding a small rectangular plastic "box" about 1x3/4 inch.mounted to the frame under the tank,closest to the seat on the right hand side,the removable lid has 3 compartments,the box itself has 6 holes, in five of them there is a wire one of which keeps sliding(falling) out and nothing in # 6 opening .I have looked in the clymer for clues but can not identify

I have the same mystery "box" on my 85 R80RT. The Haynes manual shows a "connection for special equipment" 5 lead connector, leads coming in, nothing going out. The leads appear to connect to: ground, ground, handlebar switches, handlebar switches, and a double connection to main fuse and rear brake lamp switch from one terminal. A connection for police lights/equipment?
Rick at Motorrad Elektrik could no doubt confirm it's use.