Dude I'm guessing this must be your first two stroke. You just got to keep those rpm's up don't ride it like a grandpa rev that bitch she can take it. Oh and it doesn't want to start out in 2nd then don't start in 1st or get gears. I droped a tooth in the front cause I like acceration over top end I probably could start out in 3rd but I don't.
Oh and for mods I just did mine and I was right in your price range. I did a dune port, wiseco pistons, hotrod crank, cool head, gears, and luckly I had t5's on it when I bought it and I love it. I needed that power coming from my cr250 and cr500 got hurt to many times mx track now I'm on 4 wheels. I am loving it thought got to love the dunes on a banshee.
Sorry got rambling on just my 2 cents