'77 r100rs headlight/ tail light issue

[gpr100rs]

Roused my '77 r100rs out of its slumber, headlight and tail light won't come on. When in "parking" mode, front parking and rear tail light come on. When switched to full on position, both go off and headlight does not come on. I can flash the high beam but it won't come on when when I switch to high. Thought I'd throw out before running thru some diagnostics. My initial impression is it's the relay?? All worked when parked last fall.

[jagarra]

I just had a similar problem with one of my bikes. A little contact cleaner in the switch cleared it up. Electrical switches when not used may develop some oxidation on them. Spray some contact cleaner in there and exercise it through all the positions.

[SteveD]

Willkommen.

Are the instrument lights also off?

Check your fuses.

The first R100RS is 40 years old this year.