XR400 electrical problem
 

My headlight,tail light and speedo light work fine.
brake light is barely visible, you can see the filament glowing orange but thats about it, and the horn wont work despite a new handlebar switches.
any ideas what it might be?
all connections are clean and make good contacts.
where do i look to trace the problem

XR400 lights
 

If anyone out there has a US spec XR400 they won't honk a DC horn and they don't have enough current at idle to make a brakelight get bright. The US spec doesn't have a battery and the lights run on AC. So for a horn get a old moped horn, it will run on AC and for a brake light rev the motor up and find a lower draw tailight/brake light. Some times this is done by wiring in two small sockets so you can run two low wattage bulbs...one for tailight and one for brakelight.

thanks for the advice.