So I strip the clutch and remove the kicker cover to check the thrust bearing - nothing obvious. However I end up replacing the pull rod (had some wear around the rod about and inch from the thrust bearing end??) clean all the components and refit. Running a 5 finger clutch, alloy pressure plate, and the notched nut adjusting plate, which has worked for the last 10 years.
All back together, I can select a gear and bike moves forward BUT it wont go back when its in gear and clutch disengaged, if it does same loud clicking noise and lots of resistance.
Before I strip it again does anyone have any idea what it could be????