LST Forward Only Transmission FAQ and Mods

[lincpimp]

Ok, so we have covered tranny internals, now onto the fun stuff!

For my new project I decided that I wanted to retain the high/low function but remove the reverse gears. The high/low function is manually selected by a knob on the tranny, and reasonably simple in operation. The 2 gearsets are in constant mesh, and a stout dog clutch engages between the gears, so it is sturdy enough to handle brushless (IMO).

So here is the stock tranny pic again:



And here is the tranny with the reverse gears removed and a few simple spacers in place to hold the forward/reverese dog clutch in place so that it is in constant engagement with the forward gears.



Here is a pic of what I used to lock it in place. A 8x12 bearing fits over the shaft perfectly and hold the sliding clutch against the forward gear. The al spacer is a cable stop, happened to be the exact length to fill the area the reverse gear left. Alternately you could just leave the reverse gear in place. I drilled the center of the cable stop out with a 15/64 drill bit so that it will match the 6mm shaft. After that I just use a traxxas teflon washer to take up the slack in the top shaft between the bearings, it is placed between the cable stop and the left most bearing.



So now we have a tranny with the hogh/low selector and no reverse gears, or selctor. That means the forward/reverse servo can be removed. A small plug or tape will be required to cover the 2 holes left by the removal of the forward/reverse shifter and the lower reverse shaft outer bearing.

I will detail the locking of the second gear clutch in a few, that way we can remove the mech brakes and servo and use motor brakes.