need help FAST with a new bike

Rich said it best. As a starting racer, unless you are a one in a million rider, you will not ride any bike to its potential on the mx track. The bike does not have to be fast, it has to be reliable and handle well. My vote is for a well kept 125 2 stroke. Since you have an 85, the 2 stroke power will not be alien to you, as it would be for someone moving up from a 4-stroke playbike (ttr, etc). Recently, my son was smoking a guy on a 450 at the track on his 125 (the day he figured out what I am trying to tell you). It all comes down to rider skill at the junior level. It has nothing to do whatsoever with bike. Period. A two stroke will be easier to maintain, generally, than a used 4 stroke racebike. Like most young people you are all caught up in "bling". Forget that crap and be realistic. Racing is expensive. A good 125 will be less expensive than a 250f in the long haul. The Yamaha is supposed to be the best 125. I haven't ridden one, but I sure know there is nothing wrong with a Honda or KTM 125 either. Probably nothing wrong with any of them. It's all about set-up. :)

my 2c

FIM, http://www.fim.ch/en/default.asp. You need to post a thread about getting going racing down under, http://www.dirtrider.net/forums3/forumdisplay.php?f=63. And lastly, if it was me, get a YZ-125.

Yeah Im 6.0ft and on a 300exc at least a 125!!

I'm new to this forum but have you made your choice yet? Here are my 2cents. If you have never raced and had to deal with other riders on the track looking to take positions it would be best to start out on a bike you were really familiar with. When you get where you can move up through the field. Then go get yourself something bigger be it the 125 or 250F learn how the bike handles out of compitition once you get the feel for the bike head for the races and eat em up. nothing worth winning comes quick or easy. If you jump into compitition on a bike you don't know I'm afraid your going to be facing a huge disapointment and don't want to see you lose your love for riding. I know at your age you want to go bigger RIGHT NOW, but I think you'll be happier if you ease into the race scene and work your way up. On the bigger bike you'll be against older more experience riders and will pay the price for it. On the smaller bike even though your a big old boy you'll be facing riders your own age and experience level. Good luck and keep us posted on how you do.