Ok I have a 2009 zx10r, pc3, -1 sprocket up front, lowered, jardine gp slip on, k&n. I was thinking of stretching it, I love the drag strip and most my friends bikes are stretched. My question is what chain to use and how long to go? Is the 520 worth the weight or do they break easy? Its got a rk 525 now. I was also trying to decide what sprocket set up, I was wanting to be able to switch between 2 set ups and use the same chain, but will have to chage the length of extensions. I want one for 1/4 set up and one for gas/cruising. Is it possible? My goal is to get mid 9s at 140+ on the bike, I weigh about 180, and suited 195 at.most.