How fast does a 50 hp outboard motor go?

Speed is dependant on a number of factors. Most importantly the size, type and weight of the boat that it is on and the number of people on board. A 50 HP outboard will push a small aluminum fishing boat a lot fast than it will a 20 ft fiberglass boat.

I have a 50 HP 2 stroke that will push a 16 foot aluminum boat 35 MPH.