These two gears were previously pinned through the titanium shaft with hardened dowel pins and setscrews. Because of the gears realatively large diameter compared to the shaft diameter, a large amount of force was being translated to those pins. This part of the modification will pin the two gears to each other with a precision spacer in between eliminating this transfer of torque through the pins and shaft.

I had to cut the spacer from precision .010 thick 302 stainless steel shim stock on the wire edm.

I used a short piece of 1/4" drill blank to preset and align the gears. I used the setscrews in the gear hubs to hold the gears in place to be pinned.

Here they are preset and ready to be pinned.

First I used an EDM drill to blast two "pilot" holes through the stack.

I then used a wire EDM to size the holes to .0002" smaller then the dowel pins I will use to create a perfect press fit.

This picture shows the screen on my FX-10 Wire EDM machine which is currently cutting the holes using my Hole Macro Program. I cut and size holes very often so I wrote this custom programs that just requires a couple of variables to be set and it calculates the tool path and settings automaticaly. Just add a length and the same program does slots too!

As you can see here I am pressing 3/32" diameter hardened stainless steel dowel pins into the precision holes permanently (they can be pressed out) The two pins are on a .688" bolt circle so now the torque will be transfered from gear to gear through those pins instead of the shaft. Thats the last time I will touch those gears!

As you can see here to do this modification I had to completely disassemble the tranny to get the gears out. This picture shows the newly pinned final reduction in place at the bottom of the tranny and the shift shaft and gears ready to be installed.

This picture shows the secondary reduction in place. This is the shift shaft that moves to allow two different reductions, high and low gear.

Heres another view of the shift shaft and the shift box and sleeve ready to be installed. All the gears are pinned through the shaft and setscrewed with Loctite 262.

The shift box positions and holds the shift shaft inplace to keep the tranny in either high, neutral, or low gear. Neutral (shown) is especially cool for the bench, see how the smaller middle gears on the shift shaft are stradling the gear on the lower reduction?

This picture shows the tranny in low gear with the main shaft inplace. The large gear sticking out the end of the tranny couples with the motors (2) pinion gears to form the first reduction.

After all the gears got a nice coating of Team Losi white Teflon grease I put the cover on sealing the tranny from the elements (on the top anyways).

To take the tranny out pretty much means taking the whole truck apart because the tranny is the center and heart of the design. Here is the rebuilt tranny inplace on the partially assembled chassis.

Check out the next page to see the rest of the 08/00 Mods and the re-assembled Bad Monkey Jr!