WTB: S5 N/A Transmission

[infernosg]

Originally Posted by Turbo II Rotor

It's a common problem with these transmissions. Replacing it with another trans seems to be the easiest way to "fix" it. I think if you take the shifter housing or the reverse sensor off you can mess with the shift fork rods and knock it out of reverse but chances are it will happen again down the line.

http://www.miata.net/garage/stuckreverse.html

This. I had this happen to my rebuilt transmission when I was testing the gears. You should be able to pop it out of reverse with the transmission still on the car but it'll be tight. There's no real fix but Mazda did release some revised parts but that will require a rebuild. The best way to avoid this is to make sure to guide the shift level out of fifth rather than throwing it back.