THE FRAME OIL FILTER At the bottom of the main tube on the underside of the frame lies the oil filter. It was under a finned alloy plate secured by four 1⁄2in nuts. It should be a metal gauze mesh, but many bikes have had the original unit swapped out for a paper element filter, as fitted to the BSA B50. There was some debate about the wisdom of this modification, as it relied on the oil pump having to overcome more resistance in the delivery path to the engine, which was why most people opt for an external unit fitted on the return side. 2.33 The filter itself was in good condition, as new, in fact. They often end up split or squashed.
2.36 The side of the gasket facing the filter unit was then greased and the filter inserted. The bottom plate had its gasket sealed to the metal, but once again, I used grease where it met the filter unit, which would make future changes easier
2.37 The cleaned and completed unit, bolted back up to the frame, ready to go.
2.31 The oil filter unit sat at the bottom of the oil bearing spine of the frame under this plate.
2.32 With the bottom plate removed, the filter unit was trapped between a pair of gaskets and, in this case, copious amounts of solidified silicone sealant – never a good sign.
2.34 All the parts were thoroughly cleaned; there were new gaskets in the engine set I purchased, so it was ready to go back into the painted frame.
2.35 The mating surface on the frame was carefully cleaned and degreased. A thin smear of gasket sealant was then added, followed by the first gasket.
CENTRE AND SIDE STANDS The centre stand was secured with two shouldered 9⁄16 bolts, which were held in place by a pair of 11⁄16 nuts, either self-locking like mine, or with tab washers on the earlier bikes. Removal was simple: I was able to hold the stand against spring pressure to get the bolts out. Once off, check that the bolt holes have not worn oval, or that the mounting lugs are bent. It is not unknown for the
2.38 The centre stand bolted on, although the design altered slightly during production.
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