The system comprises the timing rotor, pulse generator coil(s). ignition control unit, ignition HT coils, and on XL600V-T to X (1997 to 1999) models, XL650V models, and XRV750-T models onward (1996-on) a throttle position sensor. Refer to the wiring diagrams at the end of Chapter 9 for details.
On XL models an ignition timing rotor, which is on the right-hand end of the crankshaft, has triggers which magnetically actuate the pulse generator coil(s) as the crankshaft rotates. The pulse generator coil sends a signal to the ignition control unit which then supplies the ignition HT coils with the power necessary to produce a spark at the plugs. On XRV models the system is basically the same except the triggers for the pulse generator are incorporated in the alternator rotor, which is on the left-hand end of the crankshaft. The system incorporates an electronic advance system.
The throttle position sensor (where fitted) supplies the control unit with information on throttle position and rate of opening or closing.
XL600V-H to R (1987 to 1995) models and XRV750-L to S (1990 to 1995) models have one coil for each spark plug, therefore two coils per cylinder XL600V-Tto X (1997 to 1999) models, XL650V models and XRV750 T models onward (1996-on) have one twin-lead coil per pair of plugs, therefore one coil per cylinder.
The system incorporates a safety interlock circuit which will cut the ignition if the sidestand is extended whilst the engine is running and in gear, or if a gear is selected whilst the engine is running and the sidestand Is down. It also prevents the engine from being started if the sidestand is down and the engine is in gear. The engine can be started with the sidestand up when it Is in gear as long as the clutch lever is pulled in.
XL650V models have an immobiliser system which will not allow the engine to be started unless the correct key is used. The immobiliser system has its own fault-diagnosis function. Refer to Section 8 for further details.
Because of their nature, the individual ignition system components can be checked but not repaired. If ignition system troubles occur, and the faulty component can be isolated, the only cure for the problem is to replace the part with a new one. Keep in mind that most electrical parts, once purchased, cannot be returned. To avoid unnecessary expense, make very sure the faulty component has been positively identified before buying a replacement part.
Note that there is no provision for adjusting the ignition liming on these models.