Sorry, I had one for 3 weeks. Only bike I thought would benefit from a sidecar.Well this Square 4 compared to a Vincent, some good point's, Far lower Price, much less weight, very much lighter steering, will pull easily from 20MPH in fourth, lower seat height which is better for some, far easier to kick start, better side stand, better easier rear stand, and probably more,
I am a Vincent man through and through but I would NOT describe my first MK2 Square Four as "underwhelming" and only one Pheasant usually comes to look at my Shadow, three came to look at the Ariel, proof attached !
I suspect that is it. After reading period road tests about BSA's new " Roadburner" I expected a bit more. The engine is in great shape. The leak down test was excellent. It starts and runs very nicely. A10s just don't make a lot of power.Hmm, the Super Rocket engine should be good for 40 hp, in the same measuring system that gave my Special Competition Gold Star 41.7 on the BSA dyno with a 1½ GP. I swapped the GP for a 36mm Concentric which should drop that to just under 40. Although the A10 engine is a bit heavier than that of a Gold Star, the difference in power/weight with a rider wouldn't be much different. I have no complaints about the performance of my Gold Stars so I wonder if there's an issue with your engine. Either that, or you have higher expectations for the performance than I do.
Having spent a career as an experimental physicist, and having followed the unmasking of several fraudsters, I can say with a high degree of confidence that BSA faked their dyno data. I've analyzed a number of Gold Star dyno curves and they're simply too good to be true. My speculation is they carefully measured some number of engines as they did the development work on a new head, but they then created a "master" dyno curve from the results. Subsequently, they might have measured individual engines at a few rpm, but they then used the master curve to create the rest of the "data" for that engine.As with the Goldstars, all BSA a10 Rocket engines came with a factory dyno sheet.
To my thinking, it looks like a very generous and hopeful curve drawn by a steady hand used to quickly making up the dyno page for each new bike.