Thats not that bad i bought mine for 3000, 4mill cub. Rode it around the first day i got it. Took it out two weeks later, decide to race some friends on the street for fun, wanted to show what it had so i pinned it threw all the gears, held 6th for less then a second, laterally less then a second, and seized it right up. Needed new piston, domes, sent the cylinder to millennium to get nickeled and fixed, and bigger bowls for the carbs, came to the conclusion that i dried up the bowls and it seized up. I spent close to 800 bucks. I've raced it since held 6th for longer then a second and had no problems.
Year later my fucking crank decides to come apart. Luckily i found the problem before it did some serious damage. Shitty ass welds broke and the crank started to come apart, both sides.
Sucks what happen, feel your pain. Good luck.