- Spare top nut for the 3 piece tappet adjuster set. These 'lock nuts' are particular to these 3 piece adjuster sets, as they have a deeper thread depth than normal nuts of this thread type. Never the less, it is common for them to come loose, due to the high revs of the rocker arm and get lost - It is not unusual to take your petrol tank off and find at least one of them have disappeared!
Therefore sold on their own here - price is 'each'