The Royal Enfield as currently produced is a throwback to the mid 1950s, same style and engineering as the original with very little change until just this past year. The 500cc thumper is a very basic machine with British bloodlines and pretty much the performance you would expect from a mid 50s half liter single, which is to say, it could use a boost. Paul Carberry, down in Australia, had the idea of adding another cylinder and creating a V-Twin out of the basic engine, doubling displacement, giving it a satisfying sound and getting a nice performance increase at the same time.
Paul enlisted the aid of Ian Drysdale, a fellow Aussie, who you may remember builds the Drysdale V8, and together they took the concept and turned it into the machine you see here. The “Double Barrel” as it’s called, is a 55 degree V-Twin with 50 horsepower running through a 5 speed transmission. Hydraulic lifters run above the cams eliminating the need to modify the barrels. The 55 degree angle was chosen over anything tighter to provide clearance for the carbs and also for style and balance. They also retained as many standard Royal Enfield parts as possible to keep maintenance costs down.
This engine looks right at home in the bike without any cobbled together appearance whatsoever, it looks to be very well engineered. Although it doesn’t have massive horsepower, it’s an appreciable boost over stock and delivers decent performance for someone who wants the look of a classic British V-Twin and everyday reliability.
The Double Barrel requires a stock Royal Enfield Bullet as a base, then:
Essentially the Petrol tank is modified, the frame is modified (the front half of the frame is modified by us and it is a much stronger design with twin backbones , twin down tubes and also has front and back cylinder head mounts and includes the engine within the strucure). The motor is modified with a new crankcase and internals and an extra barrel and head is needed! The seat is also modified. In each case if no disc is present one is ftted.
Cost of modifying your donor Bullet is $A13,000, which currently is $8,892 in US dollars. Paul can also supply the donor bike and simply sell you the complete machine when he’s done.
I mentioned this engine project over 4 years ago!, and though I checked in from time to time, things didn’t seem to be going anywhere. Then I got a tip from Mark (Thanks!) that it looked like it was going into production. I followed up with Paul Carberry and indeed, he’s ready to build one for you right now.
The prototype has been exhaustively tested and Alan Cathcart (shown below) has put some miles on it, too. This seems to be a well done build with a little bit of a Vincent look to it. The short video on Paul’s website gives you a taste of the sound. Very classic, very nice. I like it.
Link: Carberry Enfield