on these forks the inner tube has to be in place first as there are inner and outer bushings that live beneath the seal, and the damper road bolts to the bottom of the fork. Then the fork seal has to be driven home on top of all that. When I did the FZ1 I was able to use a piece of plastic 2 inch pipe over the inner tube, that worked great as the ID was just about perfect. It's too large for this bike though.