1988 xj900f blinker problem

Dear folks, since 2 days i have a strange problem with the blinkers.
When switsched on, they blink a few times, and then seize to blink, or blink at all, and the needle of the RPM-meter sways rithmically up and down, or simply drops.
I cleaned the 2 connectors where te black wires go from 2 to 1 wire.

Maybe it is a ground problem.
Where can i find the 'further'connectors and/or the place where it is connected to the frame?

 

Main ground is on the rear of the engine.
The frame is connected by this as ground(negative).
The indicators are generally 2 wire so not a grounding issue.
I would be suspicious of the globes or indicator relay.

 

I have found it in the meanwhile, thanks!

 

Excellent!
What was the issue?

 

I think bad grounding..

 

Glad you fixed it.
It's funky really.
The spark plugs don't fire if the engine doesn't have a negative attached to it.
Actually the starter motor won't actuate either.

Paint and other issues must come in to play for the frame to not have a negative also since it is bolted directly to the engine.