The only good Norton is Norton Commander!
* https://en.wikipedia.org/wiki/Norton_Model_77_Dominator
500cc version of this reviewed 600cc variation: https://www.classicbikehub.uk/buying-guide/article/norton-mo...
By all reports a sound bike, save for some quirk that might fire both cylinders on the first catch giving a starting kick from zero to rocket in under unprepared reaction time.
* https://en.wikipedia.org/wiki/Straight-twin_engine
They had a lot of models, some were famous for racing and hill climbs.