My BX 23 will not start. I have been experiencing this for a while, when it doesn't start, it does not even turn over. I will turn the key several times and then it will start, almost like a flat spot in the starter? Any ideas?
Look at the seat switch and make sure it is closing properly.
You can add a relay between the battery and starter solenoid to provide better power to the solenoid terminal than the current path through the safety switches. I think that resolves most problems like yours.
Here is how to do that wiring.
Here is a link to an expensive version of that relay, but you can by a similar setup for a lot less money.