Fortunately this forum has some good examples of extreme load differences.
Start with minimal load situations where you have lots of motor, torque, light weight and gear ratio so low you cant shift fast enough.
Of course Joe and Hooch, probably the only Wing that can hit the rev limiter in high gear. I saw video of him idling up his drive that people could hardly stand up on and spinning the rear wheel with each piston hit.
When I saw that I knew his advanced timing would do no harm to the engine as he would never see a loaded condition. With this extremely high foot-torque to load I could see no reason to use a VOES.
brianinpa comes to mind with his easy riding style and reports about the need for less shifting in the Virgina hills and how when under a high gear load he could retard the timing vs down shifting by switching between reduced timing curves. He felt a seat of the pants increase in performance and showed how reducing the timing under load enhanced the engines torque enough the need to downshift was not required. I don't believe his bike is a candidate for the addition of a VOES. Probably in his normal daily riding he never sees the loads of the Virginia hills and the trips he does take the use of his switch or an occasional downshift would not be sufficient enough of a return for the effort. I do believe his addition of the switch will also show returns when he gets into a situation having to use a lower grade fuel and can retard the timing to match the octane.
NOTE: Never set the VOES so it is ungrounded or running retarded timing when you are cruising as you would defeat the purpose. If the vacuum hose breaks or is open and you have no vacuum to the switch you will run sluggish, get slow acceleration and poor mileage.
So when is a VOES necessary?
Brian is close, if you ride hills as a routine or change loads such as passengers, trailers or sidecars a VOES is a must.
Now, how do I wire it.
The Curves (maps) or offset from each other so the VOES controls to loaded timing and the Toggle Switch could be used to control situations of lower grade fuel.
OK I know you have some racers and you want it all, great ride, power, economy but have the need for speed occasionally. Remember went you grab throttle you lose vacuum, switch opens, timing is retarded you get as mentioned above get slow acceleration as your first 2 or 3 gears you have a minimal load and can use a great deal of timing. Add a switch to bypass the VOES to ground until you reach higher gears or the point of the engine being loaded due to gear and wind shear and then open the switch. Since you still have no vacuum if your throttle is open the timing will retard into the load.
Each of the 4 timing curves are independently different from each other, degrees timing and rev limit can be different. Any number of controls can be used to change the timing to fit load and conditions. Temperature switches for limiting RPM until engine temperature reached, NOS solenoid control with relays, timing boost control and many more.
A well tuned engine is a joy to drive, economical, environmentally friendly.
opcorn:
