my 93 accord se auto spark knocks a little with 87 octane. the car has 200000 miles on it. is this normal or should i check my valve clearance??

normaly according to my manual, all accord's should use 89 and up.
but most people use 87.

either retard your timing or get a tune-up.
or use 91 or 93 octane.

i used premium on my 86' accord.
and i'll do the same on my 88'.