Nice video here of a Seeley-Konig racer, it's also featured in the latest issue of Classic Racer.
Great example of 70s ingenuity The Konig motor was more commonly used in sidecars as it was low, compact and extremely light (the dry engine with carbs etc but without gearbox was around 20 kilos).
Nice find Craig........Tim and I went to the classic races at Chimay in Belgium in 2010, and there was a Koenig there......you're not wrong about the noise ! Awesome !
I'd strongly recommend reading the article in Classic Racer, the engine is very unusual. 180 degree crank with the rods side by side on a common crank-pin, so when the front left cylinder is at TDC, the rear left is at BDC etc.
The left-hand crankcase is separated from the right-hand case by a labyrinth seal, and the pistons on each side 'box' against each other. One big disc valve sitting flat on top of the flat 4, and the cylinders on each bank share their expansion chamber!
Reckoned to be about 80bhp, giving it better power/weight than Agostini's 500 MV at the time
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed