Unit or non unit?

[hogboy09]

I am the owner of a 1963 triumph trophy 650. my oil pump recently went out and while trying to order one i noticed i had to pick whether it was a unit or non unit engine. how do i know the difference?

[L.A.B.]

Your 1963 engine's gearbox should be part of the same casting as the engine, this is "unit" construction.

Earlier 650 year models had separate gearboxes, this is known as "pre-unit" or in the US, occasionally known as "non-unit"   construction.

A unit 650 engine number would normally have a "DU" prefix (1963-1969).      

[hogboy09]

thank you very much! it is definitely a unit engine. much appreciated