A couple of times back in January -6C my gearbox "froze" in top gear,usually soon after setting off.On trying to change gear the lever moved but did not shift gear. A bit of joggling sorted it and then it was OK.Today it did it again at normal temperature, this required stopping,engine and all,and rocking to get the box to shift.I didn't look into the gearbox before putting it back on the road, but it seemed to shift OK,only 2nd to 3rd sometimes baulking.I know BSA did a Maudes trophy which involved an M21 crossing London twice with the gearbox locked in top, but the hills round here prohibit that option. Any ideas
