With your permission Saqib bhai, I would like to add a couple of bike engines to the mix. They probably haven't won any accolades, but I personally think they are pretty interesting:
Honda NR750 750cc 32 Valve oval-piston 'V8'
uses 4 cylinders in 'V' with two conrods and eight valves per piston 125 BHP @ 14000 RPM
Ducati Desmo twins
Only engines in the world which use desmodromic (springless) valve actuation
Harley Davidson Big Twin
In production since 1914. Running changes kept it running until now. Now around 40 - 50 HP with a redline of around 4000 RPM.
Given its humble begginnings, it's the engine of choice for drag racers and speed record setters. Highest speed on Salt Flats done with a bike having twin 1500 cc Thruxton-HD engines. Speed recorded at 322.870 mph (519.609 km/h - Take that Veyron!)
Shares market with the "Revolution" engine developed with Porsche. Liquid cooled, 1130 cc, 115 HP and a redline of 9000 RPM
Triumph parallel twin.
Came in sizes from 350 to 750 c.c in the 60s and 70s, they were the "coolest" bikes around. Marlon Brando's film, "The wild one" helping along by not an insignificant amount. Still considered to be one of the most beautiful engines with a lot of "go". Spawned the first "Superbike"The Triumph Trident / BSA Rocket 3
Honda 750 4-cylinder.
Used in the first generation CB750K. Technically the second "Superbike" in the world after the Triumph / BSA. Effectively killed the market for British bikes due to reliability, quality and generally "friendly" character.
That's it! Couldn't find ten... If you guys have any ideas, please let us know!