new member with trx90 problem

HEllo rich welcome to the forums.

Right now the easiest thing I can tell you to try is unplug the run/stop switch and bypass it this will determine if you have a bad switch or not. If I had a schematic of that partiicular atv I could be more help.

Sure you can by pass that too... I just need to know how many wires and what colors

Well if you unplug the switch...on the harness side one wire will have a male end and the other a female just plug them into eachother. that ommits the switch. Example: Black/white is ignition signal from CDI unit it feeds the run/stop switch and the key switch, green is ground it feed the same switches asa well as any lights, alternator ect. if you have a headlamp with Hi and Lo the Hi beam wire is blue the Lo beam is white and Green is ground. the Tail lamp is a brown wire and a green wire. Keep in mind the Green wire feeds the ignition Coil as well and the blue/yellow or what ever other color you have is fed directly from the CDI.
Your CDI should have 6 wires , gray, blue/yellow, green/white, black/yellow, black/white, and blue/red this is going by my schematic but your may still be the same.

Anytime keep us updated.