I have a 2002 Iron Horse SGS Team. When i get to really cooking downhill i notice quite a bit of rear wobble in the rear. It feels very unstable. I think it's from the 2 piece linkage. when pulling sideways on the wheel there is quite a bit of play. Is there a 1 piece linkage for my bike? also, as a side note i'm going to go 8" rotor on the rear, what do i need to get and where from. Thanks.