So I hatched a Beldum. Upon hatching him I placed him back in the daycare to level 27. When I took him put I gave him a rare candy to evolve him. After that u went to route 19 and started training on Patrat while he has a power braver. After killing 48 Patrats killed I realized his attack has gone up from 55 to 73 and hasn't gone up any further. I have killed 10 more Patrats and it still hasn't gone up at all.

Why is this happening? I thought the most a Pokemon can get in a statement is 254 EVs meaning the state goes up by 63 points? Is this true or has it been hanged? Please help!