| Motorcycle engine design and innovation has | | | | exhaust) design.Finally, five valves per jug |
| long surpassed that of the automotive | | | | was found to be the right combination. This |
| industry, and industry observers agree that | | | | design gives the engine extra intake valve |
| the big companies like Yamaha, Honda and | | | | perimeter, which allows it to flow more air |
| Suzuki can muster considerable R&D prowess | | | | at low-to-medium valve lifts -- exactly where |
| here, which can then be applied to their | | | | valves in most production automotive engines |
| automobile engines.Competitors are especially | | | | spend most of their operating time.Honda of |
| aware of this. Says former Oldsmobile chief | | | | America Mfg., Inc., has combined plant and |
| engineer Ted Louckes: "That's where the | | | | production engineering with advanced |
| leading edge of piston engine technology is | | | | manufacturing techniques to become one of the |
| today. It's not in automobiles; it's not in | | | | leading engine producers in North America.The |
| aircraft. It's in motorcycles."The Goal: | | | | million-square-foot plant manufactures |
| Better CombustionWhen considering the | | | | 500,000 high technology engines and drive |
| advantages of a combustion chamber crammed | | | | trains a year. Kinzer noted that the plant |
| with more than four valves-per-cylinder, the | | | | produces everything that makes a car "go and |
| first inclination is to think, aha! Flow | | | | stop." He said that even Japan has no Honda |
| area! Five valves equals more flow area! | | | | facility comparable to the Anna plant. Its |
| True, to a degree, but that's only part of | | | | production, he reported, equals the total of |
| the Yamaha's design strength.In the reigning | | | | seven similar Honda manufacturing units in |
| days of the two-valvers, engine designers | | | | Japan. At present production levels, a Civic |
| would control pinging by incorporating squish | | | | or Accord engine is produced at the Anna |
| bands into the combustion chambers. By the | | | | plant every 27 seconds.Honda's iron foundry |
| 1960s, the four-valve heads of Cosworth and | | | | operates three shifts per day. The ferrous |
| Honda racing engines were allowing narrow | | | | casting and machining operations include the |
| included valve angles and thus shallow | | | | production of engine cylinder sleeves and |
| combustion chambers. Put the spark plug in | | | | brake discs and drums. Aluminum casting |
| the center, and voila!, good | | | | operations include high pressure casting of |
| combustion.Yamaha looked beyond four valves | | | | engine blocks and transmission and torque |
| to unlock even better combustion. In the | | | | converter cases, low pressure casting of |
| early '80s (Yamaha had only been a serious | | | | engine cylinder heads and gravity casting of |
| producer of four-stroke engines for about ten | | | | pistons.Joe loves his motorcycle but he knows |
| years!) it experimented with a variety of | | | | how to drive it safely. Learn more at his |
| head and valve configurations, even trying a | | | | blog here: Motorcycle Batteries and More. |
| seven-valve-per-cylinder (four intakes, three | | | | |