The Indian.

Son G painted this water colour of a classic American motor cycle from, I think, the 1920's as part of his Art College course some 20 years ago. Unframed and rolled up it lived in various lofts because of its size  (about 48 x 40 inches). Just recently he gave it to M who has had it framed and I have had the diy task of re-arranging her office wall, cutting down shelves etc to make room for it. Does anyone know what model it is?