Might not sound like a RR Merlin any more, but I thought you might enjoy this pic of
Lucky Keizer's 5 litre V Twin.
"Engine: The two end cylinders off a Rolls Royce Merlin 24litre V12 aero engine. Originally fitted to a Mosquito bomber. Making a special new crank for it took 300 hours.
Gearbox: 3 speed Holden car gearbox and engine speed clutch. Air operated.
Rear drive: Big Chain.
Frame: One off construction using engine as stressed member.
Wheels:Front: Suzuki GS1100G.
Back: Big drag slick.
Electrics: Unknown.
Starting: DC3Aero starter operated by assistant.
Carburetion: 2 x 1000cfm 4 Barrel Rochesters .
Future Mods: A supercharger and Nitrous Oxide injection are planned."