86 moto4 225

hey, i got a 86 yamaha moto-4 225, its my mom and dads and they got it for me as my first atv, i really beat the **** out of it, the motor was wicked strong but as all good things must come to and end, the motor to this day still runs, but the trans has problems im sure it has a bent shift fork.
it will shift fine 2-5 but wont go in to first. high low works great but since i cant get in 1st i cant get reverse. Its sitting along side of the shed and as soon as i get my 250r finished i was going to pull the motor and take it apart and bring it back to life again. what are your thoughts that could be wrong?

We had an Old Moto 4 and it ran forever! but it never had any shifting problems so idk. it lasted for 17 years and the wiring harness had problems . . .it wasnt worth fixing it. We beat the crap out of it too!