Castle Creations motor and ESC combo recommendations for the Tekno EB48.

Monster X w/1512-1800kv - 15T Pinion / 44T Spur on 4s = ~34MPH
Monster X w/1515-2200kv - 14T Pinion / 40T Spur on 4s = ~40MPH

Note: All speed estimates are with stock tire diameter, high quality batteries and appropriately sized battery connectors.
Always monitor ESC, motor and battery temperatures on new setups or when changing gearing or batteries.