I have a Yamaha L200txrr and get it to start. New battery cables, batteries charged, new ignition switch. Have power to lights but none to ignition key. Gauges wired to key. what could be wrong?

What about the dash lights? Did you get the battery polarity right?

Do you hear a clicking sound???NO ?? Do you have the speed ?turning handles in the extrem OUT position? Is the ground cable connected to the engine block?? Is the Red cable connected to the + Positive post on the battery?? Is the BLACK cable connected to the - Negetive post on the battery?? Why did you need to replace the fuse? Is the battery charged??

If none of the above corrects the problem replace the ignition switch

I assume that you mean that the starter will not run. Do you hear the starter solenoid operate (click) when attempting to start? If so, using either a voltmeter or test light, look for 12 volt power at the battery side of the solenoid. If none or it disappears when the starter attempt is made, check the cables from the battery for badly corroded ends. Also, check the grounding cable running from the frame/body over to the engine block for damage. If you hear no click from the solenoid, look for power which should appear at the small terminal of the solenoid when starting. If you get power, replace the solenoid. If no power, then look for a blown fuse, bad relay, bad ignition switch, or any damaged wiring. Make sure the new battery is fully charged. Hope some of this helps!

Q1. Engine will not start or is hard to start (Cranks OK) A1 -Ignition lock switch faulty -Ignition coil faulty -Power transistor faulty -Spark plugs faulty -Ignition wiring disconnected or broken -Spark plugs faulty Q2, Engine will not crank A2. Battery discharged Battery cables loose, corroded or worn out Transaxle range switch faulty (Vehicle with automatic transaxle only) Fusible link blown Starter motor faulty Ignition switch faulty Ignition lock switch faulty REMEDY Charge or replace battery Repair or replace cables Adjust or replace switch Replace fusible link Repair starter motor Replace ignition switch Replace ignition lock switch