After every 5,000 miles running (approximately) the air cleaner should be removed for cleaning and re-oiling. It should not be dismantled, as if it is taken apart and the wire element is unwound out of position it may not be possible to replace this satisfactorily, so as to get an even flow of air through it all round.
Take off the battery, the flexible connecting sleeve between the carburetter and air cleaner, detach the petrol pipes, and remove the carburetter.
Remove the nut from the bolt holding the top lugs of the air-cleaner and oil tank to the frame, and push the bolt through to free the cleaner lug.
Working from the right hand side of the machine, remove the ¼-in. B.S.F. bolt that holds the bottom lug of the cleaner to the rear engine plate.
Pull the cleaner away forward and towards the left ,springing the battery strap far enough to allow it to clear.
The entire filter should be washed in clean petrol until all accumulated dirt has been removed and should afterwards be dried thoroughly inside and out. Before refitting immerse the filter in clean engine oil (SAE50) and after draining off surplus oil and wiping clean externally refit it to the machine. No other attention is needed.