Does it have an relationship to the Curtis Honda just the frames look pretty close, JBR swingarm is much cooler with a banana in it. Curtis frames I believe were a modified HL frame.
The same man built the HLs and the Curtis bikes ~ Brian Curtis, so no surprises that they share similiar ingredients. Brian also built rather a lot of Metisse's when he worked for the Rickmans. Master craftsman is ever there was one