The Raleigh bikes of the time were basically for commuters, utility ride-to- work bikes which mainly had absolutely no servicing, and before butyl tubes generally on nearly flat tyres. The gears were rarely adjusted, and if the SA cable broke then it was left in high gear.
When repairs became essential then they were usually in a poor state. The SA used to let water in behind the cog through the bearings over the driver, resulting in being full of brown gunge. The dynohub end suffered from water and grit entering between the magnet and armature (black plastic part with the connecting nuts). This would make the dyno feel very rough and gritty, with scraping noises.
Adjust the hub by tightening the RH cone by hand until firm, and back off one turn or less, depending on where the locking washer fits over the end of the cone, one of 4 positions.
The only way to get the cone out of the LH side is to remove the magnet and armature. My previous stuff referenced above should help.
The cone is obviously fully adjustable, but needs some care due to the magnetic resistance of the dyno. The LH cone is adjusted by the 4 slotted washer, and has a locking nut.
You will need to separate the armature from the magnet to clean it. I never had one demagnetise. Also the bit about tapping down the surface of the armature to give a little more clearance under the magnet helped.
Keith
