- Team Losi Racing 22 & 22T - Mid-Motor ESC shelf modification -
By: Rob Engle
While the original TLR22 has proven popular with the pros and weekend racers alike since it's
introduction 2 years ago - in part because of it's ground-breaking LCG alloy chassis, that other
manufacturers have copied to keep pace, along with it's ability to be configured both as a
traditional rear-motor car along with the parts required to convert it to mid-motor - one of
the problems with it's narrow chassis design is its cramped interior.
While not so much of a problem if running the car in the traditional rear-motor set-up, it's
proven to be a bit troubling for those racers running high-traction surfaces and wanting to
run the car in mid-motor configuration.
We've found a modification or fix anyone should be able to accomplish to address these concerns.
This modification requires no extensive purchase of additional parts, as the rear battery tray (TLR4154)
being modified is included with the TLR 22 kit - nor does it require any special tools, as the tray can
be modified with a Dremel tool or hacksaw.
Like most, I managed to cram things under the body shell the first season I ran the car mid-motor,
mounting the ESC on the transmission brace, and watching the body swell and buckle as motor/ESC wires
were pinched each time I installed the body. Some people managed to cram the ESC and Rx behind the servo,
others used an aftermarket battery brace and mounted their ESC to it, others cobbled together some
kind of brace that hung off the tranny brace, and yet others purchased micro-sized ESCs and Rx's to
aid in making things fit - but I also wasn't particularly pleased with these other options, as I saw
each problematic in their own way.
So a few months ago, while I was freshening the car for the upcoming indoor season, I spent some time
just staring at the blank empty chassis plate - and had a brainstorm.
Since the holes used to mount the rear motor ESC shelf were the same width as the ones further forward
in the chassis used as auxiliary holes for mounting the battery stop, couldn't I modify the rear motor
battery tray (TLR4154) to use it as a ESC shelf if mounted further forward in the car in mid-motor
configuration? ... The answer was a resounding YES!
If you look at the bottom of the rear motor battery tray, there are six screw attachment points. Four forward
ones that support the ESC shelf, and two rear ones used in support of the shock tower/bulkhead. It's the two
rear posts that need to be removed (as shown in photo #1, below, see "A"), immediately behind the center
posts/screw attachment points. Afterwards, using a sharp exacto knife and file, or sanding drum, clean up
any remaining burrs or flashing remaining for clearance as these posts will be mounted very close to the
mid-motor transmission brace (as shown in photos #2 & 3, below, see "B"). Then you can attach your "new" ESC
shelf using two (2) M3 x 12mm screws (as shown in photo #3, denoted by "C"), as the front two mounting points
BUT, for those that want to attach the shelf using all four posts/screws - which is what we recommend - it
will require the drilling of two holes in the chassis 38.5mm forward of the two rear attachment holes, and
to countersink these holes on the underside of the chassis (as shown in photos #4 & 5, below, see "D").
Using all four screws has a couple of purposes/advantages: 1) it does allow you to install the shelf more
securely, 2) using all four screws can be used as a tuning aid as it does mildly stiffen the chassis, which
can be good when running on high traction surfaces, or the front screws can be slightly loosened (as with
those in the sidepods) to soften the chassis stiffness and increase overall rear traction when running on
lower traction surfaces.
One additional benefit of using this modification is that you no longer have to use both of the straps in
the two-strap system to hold the battery in place, as the rear strap is no longer needed as it's replaced
by the ESC shelf (as shown in photo #6).
I think you'll find that this modification not only supplies a more convenient ESC location/mounting point, as
there's plenty of room under the cockpit section of the body shell - it also allows for a wider range of ESC choices
as even more standard-sized ESCs can now be used, but as can be seen in the photo below where sub-sized electronics
are used the installation of the rest of the electronics isn't as cramped. Enjoy!