runesika,
The castings are a lovely & surprisingly light, its a British product, from the clutch end, the engine is heavily shrouded, but some work on designing a casting & covers for the primary side, make the engine more aesthetically appealing , the fact that you bolt the sump to the frame, means you can be creative too, my intention is to angle the engine forward, like a Rocket Three, 15 degrees or maybe @ an angle greater than this, depending on the room in the FB frame; hence, saving Cornflake packets for templates!
One of the neatest car-engine bikes, I have ever seen in print, used a four-cylinder NSU Prinz engine mated to the sump of a Ford Anglia!
Perhaps design a smaller- version crankcase- cover /sump like on the Panther 100 with heavy finning underneath. Most engine geometries, on British bikes are either, egg-shaped, triangular , oval or round, its a case of working out on the Camshaft -side what will fit and appeal to the eye @ the same time.
I even had a idea about rubber- mounting the engine aka isolastic mounts, if the drive on the right-side of the crank is used for the alternator of water-pump a wing-shaped casting/casing will lend itself to the design. Most water-cooled engines are not as appealing as air-cooled ones, look @ the Ducati range!
A modified all alloy car-engine, gives some advantages, low-down torque, which can be adjusted to where you want it in the rev band, proper filtration, low-state of tune that can be adjusted, Weber carburation, plenty of pre-manufactured goodies & mods, fairly cheap spares, plentiful tuners, & reduced stress of only having to move, (hopefully), a fully fuelled-up 450lb (max) solo motorcycle.
Seeing the Imp engine owed a lot in design to the S7/S8 Sunbeam unit which was the inspiration for the Coventry-Climax FWM (A) unit, which Mike Parkes selected as the basis for the Imp, it has links to the motorcycling world.
Further, research & development was carried out by Leo Kuzmicki, who worked with Joe Craig on Manx Norton's & was probably influential on the Norton-4 racer project, shelved in 1955/56
If the Imp-engine hadn't been forced into production too soon by meddling Politicians, the Rootes group may have been still in production today.
Lack of foresight by British motorcycle Companies allowed an opportunity to slip by, a 4- cylinder engine, modified & based round an FWM(A), could have been in production by the mid-sixties, being SOHC & over-square, it would have been a good start for the British Factories, to fend off the challenge from the land of the Rising Sun.
Incidentally the Imp engine main Achilles heal, was cooling, is not so much of a primary concern once in a motorcycle frame, increased air-flow across the cross-flow radiator, increased coolant capacity, oil-capacity & a thermostatically controlled oil-cooler, all should add up to an engine working well below its natural stress levels, which should lead to increased longevity of service.
The main reason is though it will be something different , maybe not too pretty- pretty, but attractive if you look beyond the glistening chrome of the four exhaust pipes!
Cheers
JBW
