Ok so I have a older lt160 quad and my battery was dead and I needed to start it, so naturally I bump started it and it made a nasty noise and now none of my gears work and when in gear the wheels move but the engine does not. I assume it is a bad clutch but I'm new to atv maintenance so I want some help before I order any parts.

 

Not a good idea to bump start quads. Do not order anything until you find out what is wrong. Try adjusting the clutch, you never know your luck, but if that doesn't work, take the cover off and find out if it is one of the clutches that has gone. It may be a transmission fault, I don't know the LT160, but can the chain hop off the engine sprocket?