hi im new here and need some help, i got a 2007 norco katmandu last year, and now i am starting to upgrade. i bought a new rear wheel (alexrims) and now need a new derailer and chain because they broke why riding yesturday, i want to know what a good new derailer would be, i have shimano shifters. i also was looking a new fork, the marzocchi 55 r, is this any good for light freeride/ dirtjump. thank you