from what I can tell, you wont find anything you can use at mfgsupply. affordablegokarts.com has a transmission designed for the predator for $135, which is likely to be the lowest priced transmission that is speciically designed for the predator, and possibly the only mass produced. there are other transmissions that will fit, but none that are specifically designed for the predator, unless you design your own. like I said, the tranny is $135. if you remove the gov which is recommended if you want more power, the clutch that will engage at the proper rpm is $49. with this transmission, a 12 tooth clutch, and a 56 tooth rear sprocket, you final ratio will be 11.4:1, which another member tells me will be a good balance between speed and climb. this is just one option, but its the option I am going with when I install my predator. just some food for thought.