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This thread will detail my build of a nearly completely upgraded losi LRM transmission. I was going to tack it on the end of the jrx-2 project, but I've spent more money gathering these parts than I have on some complete project cars so I figured it was worth it's own thread.

The only stock parts will be the gear case, diff access cover, diff screw, diff nut, and diff spring/belleville washers. If anyone knows of aftermarket versions of these parts please let me know ASAP.

I will be using thorp outdrive gears and diff halves
MIP small and large thrust plates and bearings as well as upper shaft and slipper clutch
Litespeed heatsink motor plate and heat-flow gaskets for the heatsink and motor
Trinity bearing kit
Losi spur gear, ball bearing supported diff gear, and aluminum transmission screw set.
I have a NIP Trinity super speedway stock motor. This yellow powerplant was all the rage at the local off-road track when it came out and everybody had to have one.

The only thing I am missing is a case to put it all in
I have a NIP grey case, but black is where it's at. I have an opened, but complete, a-3000 transmission kit. I think I may pinch the black case from that and hope I eventually find a NIP black case to replace it.

Outdrives will be MIP for the "bones" type axles, and the gear cover will of course be RPM. Both of those are mounted on the project car this is going on and so will be added when I swap the transmissions.
More pics when I get the time to tear into the packages and start building.
-Anthony

I built up the diff tonight. I have a copy of the instructions for the 3020 bearing diff kit and the mip thrust washers below.
The bearings that come in the kit are 1/4x3/8 but are thinner than standard bearings. I took a pic with 2 of the custom losi bearings next to 2 standard spur gear bearings. I have nothing to reliably measure such a small length. I looked online and could not find any 1/4x3/8 bearings in anything other than the standard 1/8" wide. The diff gear for the bearing conversion comes up regularly, but without these bearings, is not going to be of much use.
The HD small thrust bearing uses the same size balls as the main diff 3/32" There are grooves in the small thrust plates that hold the bearings inplace, much beefier than the stock 1/16" balls in the copper retainer(as if it is ever going to see power)

The instructions say to use "moly type grease" on the small thrust assembly. I used AE "Black Grease," Is that the right stuff?
-Anthony

Nice project you have there !! Pretty hard to find these Thorp gears!!

I'm having a local machineshop making all metal gear for my JRXT's trannys and xx retrofit tranny...was kind of bored to replace gears in them once in a while.

I'll post some pics when I'll get them.

I put the litesink together. It looks like I may have to trim the rpm gear cover a bit to fit flush. I'll post that up when I trim it out. For now I got some pics of the instruction sheets for the rest of the items.
-Anthony

here is a pic of the a-3000 complete transmission set.
I have 2 variations of the same part#.
This one has the 2-piece pinned top shaft/gear, the "team losi performance" logo on the motor plate, and includes diff grease
The other has the early brass pressed-on gear on the top shaft, the jrx-2 logo motor plate, and does not include diff grease.
Interestingly, both have Silver 8-32 flat head screws for mounting the transmission, and not the black ones.
I got them both in a lot off ebay. This one was opened by the seller for pictures(I hate when they do that, anybody serious about buying this stuff knows what it is), the other is still sealed. I will take the black gearcase from this for the aftermarket build in the hopes that I can eventually find one to put back in here. If it was not already open, I don't know if I would.
-Anthony

Well I finally got around to finishing this up.
The slipper pads work with "Nearly All" aftermarket spur gears per the instructions. I of course find the one it doesn't fit. No orange losi Gear on this one. I had a lightly used robinson machined gear which cleaned up nicely.
The motor is a Trinity super speedway stock motor, 23T.
except for the spur gear not fitting everything went together nicely.
When I went to install the transmission onto the car however there was a problem. The litespeed motor plate extends 1-2 mm further forward in front of the single bottom 4-40 screw hole than a stock plate. This interfered with the Robinson Racing adjustable toe-in system.
Here are some pics of the buildup.

I'm snooping around in old threads today. Just trying to relive the past (again). Anyway, what is the intended application of the orange spur gear with it's "dust rings"? I have a couple of these as well, but never really found an application for them. Just curious...