I created this mech for the Breaking Ground Walker Speed Challenge over on the KSP forums. Interestingly, the tail and neck are not just for aesthetics. I was having a lot of problems with balance and stability until I added them, and they drastically improved the efficiency of its walk cycle.
Average speed on flat tarmac is about 17 m/s.
AG1 to start and AG2 to stop. Q & E to turn left and right.
A stock aircraft called MechaRaptor. Built with 94 of the finest parts, its root part is fuelTankSmallFlat.
Built in the SPH in KSP version 1.7.2.