RC10Talk - The Net's Largest Vintage R/C Community

Is anyone familiar with the Thorp Dirt Burners 64 pitch Diff conversion? I've got one and the spacer on the shaft is too long and it won't let me close the trans case. It also protrudes past the idler gear. I've attached some pics against the factory shaft and the aluminum upgrade shaft.

i dont know the history or maybe optional parts, 'thinner' bearings etc that may be associated with it, but i have that same 64p kit ... i looked at it when i did my restoration and decided not to use it, but i do know what i would do to use it if i wanted to run it in vintage racing etc ... i would first mark it with a thin fine-edged tape to match the stock shaft WITH spacer, chuck it in a drill at a constant speed so its spinning and then use a dremel cutoff wheel to take most the material off and a fine micro file to finish it nice and square ... also, the shaft itself is too long and that needs to be cut down and the 'flats' need to be matched up ... alittle work but thats how i would do it .. as a side tip for the ultimate 'secret weapon' transmission to destroy the competition, and i did this back in the day it makes a huge difference in performance .. run composite lightweight XX4 front diff outdrives which reduces the tranny rotating mass by about half .. theres no durability problems either, they'll hold up to an entire season of racing easy ... those light outdrives with the 64p gears though would be a huge edge ...

I've thought there might have to be "thinner" bearings. I'm not sure I have a steady enough hand to start milling the gear shaft. Seems Thorp would send those bearings with the kit or there would be some info somewhere on install. Thanks for you help.

Sent you email rely as well.
But will post here in case you missed.
That topshaft is probably for XX retrofit transmission.

Looks like Thorp did do 64pitch for XX buggy and truck but pretty sure that is the Retrofit version top shaft.

I got the email and appreciate your response. Hopefully this will help more people in the future.

Just found this thread, I'm also considering the Thorp set up. I've got a retrofit transmission, so should that Thorp shaft in the pictures work with it ?
Thanks, appreciate any help

Also, I read somewhere that this Thorp conversion only works with a Hydra Drive set up, would that be correct ? Thanks

I have two of the Thorp kits. I'm going to check what versions I own now.

bird wrote: ↑Tue May 25, 2021 2:51 pm I have two of the Thorp kits. I'm going to check what versions I own now.

Thank you, I'm pretty curious