This is the type of unit fitted to my riv. The rod/button on the end is supposed to move but which way in or out. And what position is it supposed to be in when bleeding the brakes.
You may have to remove the valve and take out the large rear nut to remove the center plunger and flush with alcohol or mineral spirits....then used compressed air to blow out any remaining solvent.
Thanks,it is nice to know which way it moves,mine appears to be stuck. Amazing how a simple master cylinder replacement starts to esculate.:shock: