Dr. Robert Harms, who's work we've seen before, offers up another fascinating hybrid creation, this one is a 1938 BSA, powered by a 2002 Buell Blast engine, with parts help from Suzuki, Honda, Triumph, Royal Enfield, Matchless, Norton, IZH and Velocette! What an amazing parts pile he must have.
This 1938 BSA with a rubber mounted single, belt drive, disc brakes and modern lighting still looks like the vintage bike it's derived from. In fact, with all of these modifications, the bike probably has the all day reliability to take the doc wherever he might wish to go in very vintage style. I suspect not many owners would try that with an original 1938 BSA.
How many vintage bikes are sitting around unused while the owner waits for the correct parts, which he may never find for years to come, if at all? It could instead be on the road giving years of pleasure, not only in the riding but in the construction process itself, if only the owner wasn't afraid to work outside the box. Not every old bike needs to be restored, some simply need to be re-engineered. It's nice to see someone going his own way. Nice work!
Here is the project as described by Dr. Harms:
This is a 1938 BSA Star with a 2002 Buell motor.
The frame (or more correctly the steering head and partial backbone and equally partial front down tube is late 1930's Star of some unknown derivation (Blue, Empire, Silver but likely not Gold). The backbone was sectioned into a BSA ZB plunger rear section which is joined to a rigidly mounted Buell swingarm. The frame has no lower cradle which allows the Buell head to be rubber mounted and sets the proper distance for the stock Buell drive belt and front and rear sprockets to be used. The lack of a lower cradle necessitates the mounting of the left and right front pegs (Suzuki as I recall) to the motor as illustrated. The Buell swingarm was modified (increased in throat depth) to accept the rear 19" wheel (Honda CB750 front) which is joined to the OEM Buell rear sprocket via the large (sprocket side) and small (brake side) adapters.
The headstock was bored to accept sealed metric ball bearings and holds a BSA M20 front fork. All of the 26 tpi springer assembly hardware was remade in 1018 stainless and the right fork leg was modified to accept a Buell front caliper and Suzuki Savage front wheel and rotor.
Also note the headlight (Harley V Rod) and the LED front turn signals mounted to the new alloy headlight ears. The front and rear fenders are generic India produced alloys modified for this bike. Note that the rear fender stay is actually the fabricated alloy taillight holder and that the taillight itself is LED.
The rear carrier started life as TRW Triumph but has been widened and changed in most other dimensions. The alloy shelf under the seat base carries the resistors required for proper LED flashing. The rack also holds the plywood based vintage UK pillion (it was incorrect on my Sunbeam) and the grab handle is 1940 IZH. The rear footpegs are fabricated and the bags are restored Cravens that have a quick release system that was made to adapt them to the rear carrier.
The exhaust is shop made (front pipe started as Enfield) while the muffler is adapted Velocette with increased interior baffles.
The Buell wiring harness was modified as needed for placement and the relays and fuse box resides in the Norton Electra tool box on the left side. The actual toolbox is Matchless Brave (I think) on the right side. Using the OEM harness simplifies wiring and allows the use of the standard switch gear and the OEM electronic speedometer.
The gas tank started life as India Royal Enfield and is hand striped.
The frame is power coated blue and matched to the blue frame Thruxtons.
Here's another 2 shots of the rear wheel and swingarm, as Phoebe requested below. - kneeslider
Thanks Doc, for the opportunity to see another fascinating build!