25-02-12, 02:38 PM
A faulty CDI unit sounds the most likely cause, tricky to diagnose without an oscilloscope (not a common item in bike workshops) or a known good one to swap it with.
Alternatively, if the HT leads from it to the plugs have broken down that would result in higher voltages in the coil which will result the windings arcing. Were the leads re-used or are they integral to the coil?
Alternatively, if the HT leads from it to the plugs have broken down that would result in higher voltages in the coil which will result the windings arcing. Were the leads re-used or are they integral to the coil?