Norton Dominator 99

Hi all,

I'm new to the forum, and am looking for some information about the Dominator 99. I'm working at an independent motorcycle repair shop in Austin TX and one of my projects is a restoration of a Dominator 99. My background is primarily Triumph and Honda from the '60s & '70's. So except where the Norton shares engineering with the Triumph, I'm a newcomer

The crankshaft appears to not be stock for this bike. According to a shop manual, it's big end dimensions match up with the "lightweight" twins (1.500") vs the Dominator 99 dimensions of 1.7500". Is this a common swap, or is it more likely something that was done out of necessity or convenience? I had already sourced rod bearings for the bike, and now I will be looking for the smaller journal sized bearings, or even the proper crank if it is likely that the existing crank is too fragile for the larger motor.

any thoughts or advice is welcome


thanks,

Z.

Yeah, G`day Z, welcome aboard.
Do check out Bengies specific 650 thread, for the Norton differences you need..

Since that thread is about as clear as mud, 99 dommies came in a few versions - what year is it ?

The 99 (600cc) came out in 1955 (was it ?), and had 1.5" rod journals. Somewhere later they got stronger rods, cam, and more head finning. In 1960 they went slimline (frame).

Did they ever get 1.75" rod journals though, or was the 99 dropped in the early 60s when the 650 and the 1.75" rod journals came out. The 99SS was known for being a bit fragile in the crank dept - and even before the SS models came out...

BTW The 500 twins were always referred to as the first of the heavyweight twins (to distinguish them from the 250, 350 and 400 twins).

Hopethishelps.

I believe it is a 1960 model.

Z. Ray

Z, search for 'The 650 Norton Thread' by beng. Currently 3rd from the bottom this forum [ Other Motorcycle Classics].

So its a slimline model. (?).

Parts list till 62 says the 88 and 99 had different rods and slipper bearings than the 650.
(so hadn't got the 1.75 inch journals yet, like the 650 had).
So 1.5" journals.

There was no 99 production for 1963 ??