New to the GS500, Starting troubles

[Shadow_Splat]

Well I recently picked up a GS500 for about $400. It was not running and none of the lights would not come on. It turned out to be a fuse that was shot because they, being a tow yard, had the wrong battery and the terminals were reversed and sent the current the wrong way. So I replaced the fuse and now the lights come on but it will not start. No click and no crank. I had it hooked up to a battery jump-pack, enough power to jump a car and still no click or crank. I tested the starter relay, 3.7 ohms. And I tested the Ignition Interlocking relay, 92 ohms. Does anyone have a good place to start? If I can get it to crank over I think I can handle it from there. I'm an automotive technician but I'm completely new to motorcycles. Thanks for reading.

[AccidentalF]

Fist, check ALL the fuses, even the ones that look good, with a meter.  Jump the starter solenoid (IN NEUTRAL!) to see if the starter motor turns.  If so, disconnect and meter the control wires to the solenoid and see if you're getting 12v when you push the start button.  Give battery voltage to the control terminals of the solenoid and see if it clicks. Check the clutch, sidestand, and starter switches.  Heck, get the thing in 6th gear and see if you can turn the motor over by bumping the rear wheel with the plugs out.  Could be LOTS of things. But try the really simple ones first.

[joshr08]

isnt there only 1 fuse on a gs?

[fred]

isnt there only 1 fuse on a gs?

Yes, the GS has one fuse only (plus one spare fuse that always confuses people because it is on top of the actual fuse).

You have a safety interlock switch preventing you from starting the bike. You are either doing something wrong or one of the switches is broken. You can't start the bike without the clutch in. You can't start the bike in gear with the side stand down. It is possible that one (or more) of these switches isn't working. Check the clutch switch, the side stand switch, and the neutral switch. You'll likely find one of them broken and it should be pretty easy to tell which with a multimeter... You also might have a bad kill switch. That happens, but isn't quite as likely as a bad interlock switch...

[sledge]

If they tried to fire it up with the battery reversed the implications are serious 

The first two things that cross my mind are the possibility of frying the electronics in both the reg/rect and the ignition module and the fact the starter motor will have tried to spin in the wrong direction. Not sure what this would do to the sprag-clutch but it needs to be checked along with the starter motor itself. Also check the engine is free to turn, if it has spun in the wrong direction the timing chain might have slackened off and jumped on the sprockets.