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Two schools of thought when it comes to starting a long sleeping motor:
1) Clean the carbs, change the oil, and start kicking.
2) Clean the carbs, strip the motor down to the crank, split it, clean out the sludge trap, replace all worn parts, clean the oil tank, refill, and start kicking. That's a lot of work, and potentially a fair outlay of cash.
The danger of the first is that newer oils contain detergents that break down the sludge in the trap that is otherwise safely packed in the crank, and can send the gunk back out into recirculation, wrecking your bearings and potentially more. If your dad was a super fastidious fellow, go for the first approach with an oil without detergents from a old British motorcycle shop (don't ask here which is best
) and see what it sounds like. If not, think about the second.
The first iteration of the 650SS was the Manxman. It was export only, and very blue with a red seat. But, only that first year. Sometimes the titles reflected the year of sale rather than year of manufacture, but who really knows what happened back then at the dealer level. Smaller Dominators were available in Polychromatic Blue, but I think only in the previous decade, when the frame and body work were different and not interchangeable. A serial number would settle the date of manufacture.
