If it's anything like the 1.5L I had in my '87 CRX Si, there's not a whole lot of timing adjustment to be done on these things. Basically you need to pull the plastic timing belt cover off and rotate the crank around manually until the cam gear timing mark (an engraved/painted dot) lines up with the mark on the cylinder head, and ditto for the mark on the crank and engine block. If they're not off, then either the timing belt was improperly installed or the timing belt tensioner is getting weak enough that it allowed the belt to slip a notch ... but Hondas are usually interference engines, meaning that if the timing is off, you'll be banging valves against pistons and creating all kinds of a mess in there.
Honestly not sure if those motors allow for any real kind of timing adjustment at all or not, but if there's any to be had, I'd imagine it would be done by turning the dizzy ... although how, exactly, one goes about that, I dunno. IIRC, they're held into place pretty solid by a two- or three-bolt mount and don't really allow for any rotation like on a Ford or Chevy V8...
Now as for VALVE adjustment, that's a whole different deal. Older Hondas especially need to have their valvetrain adjusted every so many thousand miles. I remember reading that it was recommended every 15k, but I'd say more like 50k ... about the same time you change the timing belt, basically.