Navigator chain sprocket

A puller! What have you tried so far?

dan

If it is an early gearbox chain sprocket then the thread is left handed (turn clockwise to undo),. Make sure retaining tabs are flattened first. I found it needs an impact to start,

GRAHAM

hello The gearbox sprocket  should come way easy  once the tap is flated out and undo the left-hand nut  then it comes way easy  mine did and it had been stud for 35 odd years  no need for hammers with me its that easy    yours  anna j    

Left Hand Thread on the main sprocket - once the tabs are pushed back.

If the engine is still on the bike & the chain is connected, you could put it in 4th gear and stand on the brake - or if the gearbox is apart, you could try a stout piece of wood through the spokes onto the swing arm.

Or if the chain is not there ary more, you could wrap a chain around the sprocket until it binds - but beware of damaging the breather pipe above it (on an engine numbered below 106838 - the breather got moved after that number).