2. The Honda CBX Engine By: MAE 388 Design Team 5 A.Kerner, T.Doehner, J.Doyle, N.Karas Model Year: 1979

3. Key Advantages Double-overhead cams power 24 valves which feed the motor through constant velocity carburetors Only two inches wider than the four cylinder Honda CB750 it replaced, boasting a 5-speed gearbox and svelte clutch Produces 105 HP (76.6 kW) at 9,000 rpm. For a 500 lb bike, the power generation is rather remarkable If today’s sports cars possess a 10:1 weight-to-HP ratio, then the Honda CBX has a 5:1 weight-to-HP ratio; for 27 year-old technology, this is quite impressive First motorcycle engine to boast six cylinder inline configuration, which allows for the bike frame’s size to be smaller as opposed to having a V-6 cylinder configuration 6-cylinder configuration allows for a higher top end speed, horsepower and smoothness than previous inline configurations

4. Key Disadvantages Too many moving parts Extremely expensive to maintain and is rather heavy Carburetors were very hard to maintain properly

5. Key Features There are two individual gears located in the engine’s top center which govern the air intake/exhaust ports:

6. Piston Firing Order The firing sequence for the pistons is: 1,5,3,6,2,4 which leads to maximum power generation per stroke:

7. Valve Train The Honda CBX valve train is very unique in that it guides valves that can be opened/closed dynamically, thus maximizing power output and fuel consumption based on operating conditions

8. Overall Engine Setup

9. Disassembly of Engine Setup

10. Future Improvements & Considerations Overall weight reduction, which would directly lead to a more optimal weight-to- HP ratio Provide more engine torque by reducing the carburettor size Electronic ignition

11. References www.honda.com www.bikez.com www.cbxworld.com www.chuckhawks.com