Hi I am a new member owner of a 90 fxr. I have a problem with no spark, it is getting gas, turns over but doesn't fire up. Battery is good terminals are good. There is a small flat brown wire that is disconnected around the starter area that I believe comes from the back of ignition coil or that area. It is same color and style of the wire that plugs into the starter but a little smaller. Wasn't sure if that was the reason of no spark. Please help

 

Welcome to the Forum from Kansas!

This is a wire diagram I found but I couldn't read it very well, maybe you will have better luck with it.

 

Check all grounds and battery cables. If not then I'd check the
Cam sensor in the nose cone.

 

I'm not a certified mechanic...which gives you your first indication of where you should go...But if you must solve this on your own so to speak...

Before tracing down all grounds and cam sensor stuff, try focusing on that brown wire. Clearly, you're getting electricity to the system. Is there an electrical signal to that wire? either when trying to start to just with ignition on? The above wiring diagram isn't clear enough to see if the wire going to the coil is "BN" or not. But if you already see a wire that has been flattened and has broke off, or is simply disconnected, that would be the place to start. Try finding the above diagram in a larger format so you can see it. Go to dealership and ask if they have a wiring diagram or know where to find one.

Poke around a bit, you'll solve this.

 

I found a better clearer diagram just by typing 90 fxr wiring diagram. look at the black and white ones. The coil appears to have pink, blue and white wires. Check these for signal. If they have power...then maybe the coil is kaput! I see a brown wire serving the rear tail lights. do all your lights work?