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Rebuilding the Differential
The gears in the differential will wear over time. The same is true for the outdrives, driveshafts and rear axles. We suggest
using a small rag or paper towel to lay out the parts you remove to make it easier to reassemble.
Disassembly
1. Unplug the motor.
2. Remove the gear cover (three screws).
3. Remove the two screws at the extreme rear bottom of the chassis.
4. Remove the screw attaching the rear shock tower to the transmission and the
four screws at the bottom of the chassis holding the gearbox in place and slide it
out of the chassis.
5. Remove the left side of the gearbox by removing the three screws.
6. Remove any shims on the bevel gears and set them aside so they can be
reinstalled in the same location.
7. Carefully remove the large plastic sun gear and the bevel gears on
either side of it. You can use the removed differential assembly as a
guide for putting together the replacement unit (a little Losi Teflon
grease #LOSA3066 can be applied for even better performance).
8. Remove the center mounted idler gear from the gearbox. Remove
the shaft and push out the ball bearings from either side. Install these
bearings in the new gear.
Reassembly
Replace the idler gear and shaft into the center of the same right side of
the gearbox. Replace any shims removed from the right bevel gear and
slide it through the lower bearing. Replace any shims that came off of the
left side bevel gear and allow them to slide through the lower bearing as
you put the left gear box half back into position. Replace the screws and
reinstall the rebuilt gearbox using the steps in reverse order that were used
to remove it.
Changing the Spur Gear
Remove the gear cover by removing the three small screws. If you are replacing the spur gear with one of a different size
(number of teeth), you must first loosen (do not remove) the two screws that secure the motor and slide it back slightly.
Remove the 3mm nut at the end of the slipper shaft and all of the slipper parts on the outside of the spur gear as well as
the old gear. Place the new spur gear into position and replace the slipper parts. If you have changed the size of the spur,
see Setting the Gear Mesh below. After you have changed the spur gear, you will have to adjust the slipper as described
elsewhere.
Changing the Pinion Gear/Gear Ratio
Before you change the pinion gear ask yourself why you are doing it. In general, if you change to a larger pinion the top speed
will improve but you will see less acceleration and run time. This would only be advisable for really long track layouts with few
tight turns. Changing to a smaller pinion will give you quicker acceleration and possibly a bit longer run time but a little less
top speed. This would be good for short layouts or when running hotter motors. The pinion on the Mini-Late Model offers the
best balance of both. To change the pinion, remove the gear cover, loosen the motor screws, and slide the motor back. Use a
pair of small needle-nose pliers between the motor plate and back of the pinion to push the pinion off. Place the new pinion
on the end of the motor shaft and, using the flat of the pliers or a similar flat tool, push it on to the same position as the one
removed. See Setting the Gear Mesh below. Your Mini-Late Model comes equipped with a 16-tooth pinion, while this pinion
gear is optimal for most tracks you may find that the included 12-tooth and 14-tooth pinion gears can be advantageous on
shorter tracks.
Warning
: When running aftermarket motors, check with the motor manufacturer for correct gearing. Never over-gear
the motor as it can cause overheating, damaging it and the speed control.
Setting the Gear Mesh
The motor screws should be slightly loose. Slide the motor forward allowing the pinion gear to mesh
with the spur gear. Snug (not tight) the bottom motor screw and try rocking the spur back and forth.
There is a slight bit of movement before the motor is forced to turn over. If not, pull the top of the
motor back slightly and recheck. If there is too much slop between the gears, push the top of the
motor forward. When set properly the wheels can be spun forward freely with very little noise. Make
sure to tighten both motor screws and replace the gear cover before running.
To Remove Transmission
To Remove Gear Cover
