1991 accord ex-r 5-spd

hey guys, im having trouble with my idle, at operating temperature, it sits @ around 550-600rpm, which is in the low range of the oem specs., but it just seems too low, the car shakes too much for my liking, i would like for it to be quieter, everything shakes. How can I adjust my idle properly ? or does it have to do with something else ? I just had the timing belts done @ 292k, and I know it a bit tight, could that affect anything ? the idle was a bit better before i changed the belts. Let me know what you think

thx, Frank

 

Tight belts could cause a funky idle.

Idle adjustment here..
https://honda-tech.com/zerothread?id=2215762