Head on over to
ZRXOA Home Page ... parts are NOT hard to come by on there. It's also a true example of shadetree mechanics and parts manufacturers. The enthusiasts for these bikes are just awesome, fabricating some of the sweetest things i've ever seen.
it's stock a 5 spd, but there was a guy making a custom 6 spd tranny for them. PRICEY? sure, but the cost was totally worth it.
Torquey doesn't even begin to start. This thing is like a buell off the line. it's obscene. I spent 3 months on mine and never went over 8 grand on the tach. I want another couple bikes (big cruiser, and a nice triumph 675 and a dual sport) but the ZRX will ALWAYS be in my stable. I bought mine at 14k miles, and I'm around 40k now.
If you need help finding one of these or parts, let me know.