Motorcycle Repair: 1979 honda twinstar, turn signal switch, brake light switch

Question
I have a 1979 honda twinstar turn right side will come on maybe flash but mostly stays on left side nothing flasher makes buzzing noise tried 3 flashers same thing is still 6 volt checked when turn on left side checked wires no power going to them any help please

Answer
Darrell,  
Start with a fully charged battery.... should be about 7.2v fully charged with no load. If your battery is low, the charging system will not charge the battery AND run the lights, etc, unless you are driving at 65mph for about 10 hours straight.

Check bulbs for continuity and that all sockets are clean and shiny inside, then check all the ground paths from the bulb base, back to the chassis. Turn signal units have to be grounded or have a ground wire heading back to the chassis ground.

If you have some power to the right side and nothing to the left side then the turn signal switch is probably dirty or corroded inside the contacts. Pull the headlight unit or fuel tank to get at all the wiring connectors. Check and clean all connections. If the bike has crashed, often the turn signal switches get damaged. They usually can be disassembled and cleaned if you are careful and have good tools.

Circuit:  
Battery-Ignition Sw- Flasher -Turn signal switch- to left or right side wiring to GROUND.

Blue wires are for right side/orange is left side lights. Blue/white or orange/white are running lights, if equipped.

Be sure that the brake light switches are not in ON condition when the key is turned ON. There is a separate switch for the front brake lever and one for the rear brake linkage. Rear is adjustable and are often not set properly so your brake lights are on all the time and draining the battery even while you ride.

Front brake light switch probably has a small plunger that contacts the lever when it is released. The tips break off and then the brake light stays on all the time. Replace the switch in that case.

Bill Silver