Hi,
I bought Electron gear set for my Joker. It is not a drop-in replacement for the stock JP gear.
I had to add plywood to the mounting spot in the wings, for the mounting flanges of the Electron are completely different than the stock gear. BTW - the stock gear was pre-mounted from the factory and they didn't do such a great job at it.
Now I found the Electron legs are 1cm too long. Yikes! I think I can re-drill the wheel axle hole and make it work, Or, I can shorten the leg at the other end. I don't have a mill, only a lathe a drill press, so I got to figure which is the easiest with what I have.