The do's and do not's when shifting

[remulasce]

Shift down when you encounter resistance (another robot, etc)

Well. Shift before you encounter the resistance. It's hard/impossible to downshift once you're already in a pushing match, due to forces on the shifter locking you in whatever gear you were in.

Shifting for acceleration (gunning it in low and then shifting to high) doesn't generally pay off well enough to justify it.

I've done this before. It depends upon how high you gear high gear, if it's too high then you'll need to start in first and shift up. But definitely keep in mind, one side of your drivetrain will always shift before the other, due randomness of the dog slot and your robot. So if you shift up to high speed without letting off the gas, you may find yourself facing a different direction than you were before shifting...

Make sure to slow down before you shift in matches. Shifting from high to low while moving fast tends to cause wear on the gears (they grind).

Advanced mode: Purposefully return the controls to neutral/brake and downshift any time you need to slow from high speed. This allows you to slow down without inputting motor power (except for the internal electric brake). If you slow down by inputting reverse power, you may quickly find yourself tripping your motor controller overcurrent protection.

The 'gears' won't grind, and the mechanical people can replace the shift mechanism after every match no problem.