Norton Dominator 99 1957 - Dual Seat

The seat is not attached to the rear mudguard. There should be rubbers, on the frame rails, and the wingnuts pull the seat down, firmly, to sit on these.

On my 1956 99 the dual seat presses down on the mudguard when the nuts are done up. I think it is by design.

Possibly the rubbers, on the top rails are too thin. On my '54 88, the seat does not contact the mudguard at all.

Previously John Shorter wrote:

Possibly the rubbers, on the top rails are too thin. On my '54 88, the seat does not contact the mudguard at all.

Well I went and took a look. There are no rubbers at all.

Sorry, on the earlier models, there a half loop support, for the rear mudguard, attached to the shock absorber top mounting. This has holes into which are inserted domed (mushroom type) rubbers. The base of the seat sits on these, not the mudguard. If you make it to the Begonia Rally, you can see exactly what I mean.

Oddly enough, I parked next to a 1957 88, at the Begonia. Jonathon is right, the later models do not have the same seat support, and do seem to sit on the mudguard. I think I would put a pad on the mudguard, to prevent any possible chafing.

Just the two wing nuts make it fairly easy to access your tool tray. I never had any trouble with my 1959 99 but I did eventually buy a new seat from Leightons. Their only mistake was to use UNF threaded studs instead of BSF! DOH! It means I then had to look for UNF wing nuts after taking years to find a second original brass one to replace one I'd lost in 1970! Their seat is an exact copy of the original (Mine was 1959) even down to the red piping with its textile fabric cover (Not PVC). They obviously use the original rollers for the black seat covering. Best to use penny washers or rubber-faced washers under the nuts. The rubber needs to be either 1/4" sheet or about 3/8" dense foam along the frame tops. AS long as the seat has a flat bottom it should be a snug, fully-supported fit.