Yamaha T60TLRD missing at all rpm

[busheland1]

2005 T60TLRD started missing intermittently. Checked peak volts, resistances etc on ignition system, all looks ok. No problems found in fuel system. Used an inductive timing light to try to narrow focus and found erratic, extra sparks on two of the four cylinders. Anybody seen this, suggestions for further tests

[99yam40]

I would use a peak reading volt meter made for these ignition systems and read all inputs and outputs of the CDI to make sure they ar in spec

[busheland1]

Ok, checked the Pulser coil output ( cranking with connector unplugged ) and measured in a range of 7.9 to 8.1 vdc. I can understand the voltage being low would cause issues but how about slightly high? The resistance of the Pulsar coil measured 523 Ohms ( looks ok given the reference in manual ). Still working on the ECM output values, I only have voltage values for "loaded" which I assume means the connectors plugged into ignition coils.

[busheland1]

Pulser coil air gap measures around .5mm

[99yam40]

Yamaha and others show minimum spec, over is usually not a problem from what I have read and seen.
did you measure the charge coil inputs to CDI/ecu?

does this motor have more than one charge coil?

you can test loaded by sliding a small pin or straightened out paper clip into the backside of the connector where the wire goes in and clipping your lead to that, make sure you do not damage the wire and/or connector insulation.

monitoring some of those voltages when the problem shows up would be a good idea.