Thanks for responding. Yes, the dowel locates into the hole in the underside of the bar, but I’ve just found a video of someone replacing the switch on a Tracer 900. Inside the switch this shows a metal saddle clamp over the top of the handlebar which screws through the two holes at each end of the plastic piece with the dowel, then into the captive threaded inserts in the lower half of the switch. When the saddle clamp is tightened it fixes tightly the bottom half of the switch to the handlebar. The two screws accessible from outside the switch then just join the top half of the switch to the bottom half - they’re nothing to do with fixing the switch to the bars. I just wondered if anyone had looked inside their switch on an ST to see if there is a saddle clamp which fixes the bottom half of the switch firmly to the handlebar (before joining the two halves together with the long machine screws outside the switch).