motor mount Question!?

ok so i just rebuilt my motor on my 03 660 and when i went to put it back in the frame the rear motor mount did not sit in the swingarm correct...i put the bolt through and tightened it up and there is still about 1/8-1/4" on each side where the motor has back and forth play...can anyone tell me why this could be happening or what i am missing..i checked everything and cant figure it out