Before going down the CX route, consider the fact that it is a pushrod motor (not even SOHC) and it has shaft drive severly limiting gearing changes.
Sam.
EngineThe CX series motorcycles feature a crankshaft configuration aligned longitudinally with the axis of bike, sometimes called a "flying" V-twin, because the cylinders point up on either side of the motorcycle but are not symmetrical. The CX was the first V-twin motorcycle that Honda ever built. Honda built a prototype CX350 but it was never released to the public. In that version the cylinders did not have the characteristic 22 degree twist.[1] Initially conceived as having a full 90 degree angle between the cylinders like the similar Italian Moto Guzzi machines, early testers reported that the prototypes were too smooth. Also, the carburetors, which projected directly rearward from the cylinders, tended to interfere with the knees of riders. Subsequent engine designs had their V-angle tightened somewhat to 80 degrees, and the heads twisted inward at the rear by 22 degrees.
An innovative design places the crankshaft above the transmission, with both in the same housing. This keeps the engine short but quite tall.
The engine design combines a 10.0:1 compression ratio and 9,650 rpm redline with overhead valves and a camshaft nestled at the base of the V between the cylinders. There are four overhead valves per cylinder, with unique forked rocker arms acting off each pushrod. The engine runs well on 87 octane petrol. It delivers nearly 50 hp (37 kW) at 9,500 rpm with high low-speed torque characteristics. Moto Guzzi, with their contemporary V50 Monza, delivered 48 hp at 7,600 rpm. This was from an aircooled, 2-valve 90° V-twin. This Guzzi model is little known outside Europe, so a direct comparison with Honda's CX500 is possible only on paper or amongst motorcycle enthusiasts.[2]
The cylinder bores are cast in the crankcase which complicates the overhaul process although many examples have gone 200,000 miles or more without any major engine work.
[edit] TransmissionThe transmission spins opposite the engine crank to counteract the engine torque's tendency to tip the bike slightly to one side when the throttle is opened or closed. The gear shift lever is moved with the usual up-down motion of the left foot, but instead of rocking in a forward-backward motion as on regular bikes, it moves left-right. This difference is transparent to the rider, however, and requires no change in shifting technique. It also means that it is not possible to adjust foot peg and gear lever setup when personalizing riding position.
Power is transferred via an enclosed splined driveshaft with one universal joint. The shaft drives a bevel gear to which the wheel is joined via a cush-drive, which absorbs and dampens driveline shocks and vibrations. The bevel drive spins in an oil bath, and a zerk fitting is provided for greasing the shaft bearing. This reduces the motorcycle's maintenance costs.
