i used to RACE a 1986 suzuki quadsport 230 bored out to 250... it was a great bike, we had dick cepek spiders on the front with 19' wooly boogers on the rear. my best finish for the NEATV-MX series was 4th outta 39 200-250 class.
the only thing that sucked about those vintage suzuki's was the swing arm. total shit, if you didnt get it reinforced. the frame-side bushes would go and then the chain would be thrown. it took out our side cover many times... we even had a huge steel chainguard in there. the chain got thrown with so much force once, it snapped the bolts holding the guard on.
those are great CHEAP bikes, and respond well to mods. its a 4-stroke btw. massachusetts state law tells me that once you register your quad, you get a plate with a sticker on it (just like cars, but its not actually inspected). that plate/sticker allows you to ride up to 500ft on the road between trails.
if you want any other info, pm me.