Richard, the Triton made use of a Triumph engine and a Norton Featherbed frame. The early version of the Norton frame had two parallel top tubes that ran from the headstock back to pick up the rear spring/shocker mounts and as such it was quite wide in the area of the riders crotch... Whereas in the later versions of the frame the top tubes were waisted approaching and leaving the critical area in order to facilitate a more comfortable seating position for the smaller rider.
Exactly that.
They were later designated either "wideline" or "slimline" featherbed frames.
