The Honda CBR250R ignition system consists of power unit, ignition coil, battery, ignition switch, spark plug and pulse rotor. The Honda CBR250R has a digital unit with a built-in micro computer provides best ignition throughout its operating speed range. A pulse has seven projections. From (1) to (7) have 45 degree separation and 90 degree for (7) to (1). The engine rpm and crank position for each cylinder are detected from the relative position of the seven projections and two pulser coils. The two pulser coils are installed so as to have 15 degree inclination from level line for PC2 end, compared to PC1. This angular offset is to detect crank positions.
The time when the pulse rotor’s projection passes the PC1 pulser coil is reffered as “O-reference”. By detecting the time required to have the projection at the pulser coil again, the engine rpm is determined and the micro computer determines ignition timing. The following diagram shows detail schematic and wiring diagram of Honda CBR250R Ignition System.