Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision | Next revision Both sides next revision | ||
|
techtalk:evo:engctl01 [2019/08/05 21:09] ixl2relax [Electronic Ignition Systems] |
techtalk:evo:engctl01 [2019/08/06 13:27] ixl2relax [Electronic Ignition Systems] |
||
|---|---|---|---|
| Line 8: | Line 8: | ||
| ===== Factory Ignitions ===== | ===== Factory Ignitions ===== | ||
| ==== Electronic Ignition Systems ==== | ==== Electronic Ignition Systems ==== | ||
| - | **(1980 to 1997)** Components include a timing rotor (timing cup), sensor plate or inductive pickup, ignition control module, ignition coil and spark plugs. For electronic advance, the inductive pickup generates TDC pulses that are sent to the solid state Ignition Control Module (ICM). The ICM computes ignition timing advance and coil dwell. A Vacuum-Operated Electric Switch (VOES) is used (since 1983) to switch between 2 different spark advance curves built into the ICM. ((1959-1985 Clymer Sportster Repair Manual pg 229)) These advance curves where modified over the years as indicated by the Curve Letter (such as G, J, K, Q). The variation in the model numbers were sometimes to designate different terminations of the cable (such as direct wire or 7-pin plug or 8-pin plug). | + | **(1980 to 1997)** The components for the ignition system includes a timing rotor (timing cup), sensor plate with an inductive pickup, ignition control module, ignition coil and spark plugs. The inductive pickup generates Top Dead Center (TDC of piston) pulses that are sent to the solid state Ignition Control Module (ICM). The ICM computes ignition timing advance and coil dwell. A Vacuum-Operated Electric Switch (VOES) is used (since 1983) to switch between 2 different spark advance curves built into the ICM. ((1959-1985 Clymer Sportster Repair Manual pg 229)) These advance curves where modified over the years as indicated by the Curve Letter printed on the modules (such as G, J, K, Q). Some of the variation in the P/N was to designate different terminations of the module cable (such as direct wire or 7-pin plug or 8-pin plug). |
| The ICM for these years uses a Dual-Fire Spark system. The dual-encapsulated coil is fired by only one coil trigger wire from the ICM. This produces a spark on both plugs at the same time, regardless of which cylinder is currently under compression. Therefore, there is a dual-spark created when the front cylinder is near TDC and there is another dual-spark created when the rear cylinder is near TDC. ([[techtalk:evo:engctl01#ignition_coils_-_specs_checks|See coil information below]]) | The ICM for these years uses a Dual-Fire Spark system. The dual-encapsulated coil is fired by only one coil trigger wire from the ICM. This produces a spark on both plugs at the same time, regardless of which cylinder is currently under compression. Therefore, there is a dual-spark created when the front cylinder is near TDC and there is another dual-spark created when the rear cylinder is near TDC. ([[techtalk:evo:engctl01#ignition_coils_-_specs_checks|See coil information below]]) | ||
| - | The spark advance starting point can be altered by physically rotating the sensor plate which is located in the 'nosecone' behind the round cover. | + | The spark advance (curve) starting point can be altered by physically rotating the sensor plate which is located in the 'nosecone' behind the round cover. |
| ^ Ignition Control Modules (Latest Known Superceded Version) ^^^^^^^ | ^ Ignition Control Modules (Latest Known Superceded Version) ^^^^^^^ | ||
