I had a 1980 model, and raced it in '81; I "tried" anyways. It was the without a doubt, the biggest POS motorcycle I have ever owned, or even known about. In four races, I trashed four top ends. The only good luck I had with the bike was when I was selling it, some guy stole it and I got $75 more from insurance than I was asking. :)
Other riders had similar experiences, and by '83, the Yamaha IT, Honda XR200, and CanAm were the popular 200cc weapons of choice, despite that the KDX was a 200 and would smoke the 175s on top end power.
Problems- Clutch throwout bearing goes south w/o notice; brakes are gone if you even say the word "water"; exhaust o-ring is always in a new state of leakage, giving a continuously changing powerband; gas tank will get melted by exhaust pipe; linkages will bend under hard hits; and the top rocker arm bushing wears quickly IF the POS actually runs long enough.
The only good thing was that parts were cheap for the time, but you needed SO many.
As you can tell, I would suggest just about any other bike. :)