Primeape: Thunderbolt? Has Primeape really enough Special to effectively use it? You might want a Fighting STAB instead, sadly the only thing it still gets is Submission which is far from good. Another improvement you could make is replacing Trash with Hyper Beam, in this generation it's a decent choice.
Machoke: Looks like a filler Pokemon to me (the moveset makes it look kinda neglected), so don't know what to do here
Machamp: Machamp has monstrous attack, get something else than S-Toss. Too bad that, again, there's no real alternative to Submission...
Poliwrath: Since you can't get Amnesia anymore because it's already evolved, I'd say leave it as it is. It's fine that way.