Transmission kicks out of 1st only
 

I have a 04 rx8 80k miles, recently hitting some issues with the 6 speed lost 1st gear a week after i was hit rear driver side right on the tire... 1st gear only works if i take off really slow or down shift but once i hit the gas a little it kicks it out no grinding just kicks it right out every-time all other gears work perfectly. The clutch pedal and a exedy stage 1 clutch kit were added a month before the accident... so i'm stumped

It's likely bad syncros in the tranny. You replaced the clutch pedal? Who installed the clutch?

both were installed by a mazda dealer

Check the forks.

what are forks?

what you eat with.

they are the shifter forks in the trans to select gears