Collocations for speed limit - noun

high, low
legal
50-mph, 60-mph, etc.

drive (AmE), keep to, keep within, obey, observe
break, exceed
Motorists can be fined on the spot for exceeding speed limits.

set
raise
lower, reduce (esp. BrE)

above the speed limit, over the speed limit
He was driving over the 60 mph speed limit.

below the speed limit, under the speed limit, within the speed limit (esp. BrE)
You have to come down that hill in a low gear to keep within the speed limit.