I currently own a stock r6 street bike and have been doing some track days. My question is if I turn my bike into a track bike what is tthe first things to start changing since I can't do it all at once? Or am I better off just buying a bike that someone else has already built?
It's usually going to cheaper to buy a bike that's already been sorted out if you have to start from scratch. If you want to convert a bike then my recommendations are: Tires Brake pads Brake lines Body work Suspension In that order. There are some fast people out there with mostly stock bikes.
Better off to buy an already prepped bike but if it comes to it... Bodywork...doesn't need an expensive paint job, just pull it all off and sell it along with the lights to finance other bits... Make sure you have good gear and a back-up helmet. Remove coolant/antifreeze, replace with water. Tires Service brakes (ss lines if you can afford) Service suspension (fork oil change) Safety wire the biggies (oil drain, axles, oil filter, etc) Give up any and all sentimentality to the bike, it might leave the track in a dumpster, so have that mindset. Also, if you think you need to upgrade you suspension or "xyz" to get faster but you haven't been to a school or one on one coached; spend your money on YOU first. You, yourself are the biggest single limiting factor of you bikes ability to get around the track as fast as possible if you keep it in good shape and keep good tires on it.