I have the Haynes service manual and tried to follow that to a T. I bought a Stant cap today and put that on. Still doing the same thing. I'm guessing I should suck it up and buy the Triumph cap just to make sure. Right now I am limited on space and time to try to get this figured out. I'm just hoping that it isn't the head gasket. Every thing that I'm reading on this is pointing to the rad cap. I'm more than likely just gonna get this thing to my local bike shop and let him test, flush, and work the system just to be on the safe side.
2002 Triumph Tiger 955i
2001 Triumph TT600/ for now :(