Continued ignition woes

[xs650newb]

Hey everyone,

As I've said in previous posts I've had trouble getting my newly rebuilt engine to start. Compression is good, valves, and camchain are set, and the carbs are clean.

I am letting the engine turn over with the starter motor and I pulled a plug and grounded it to the engine. The spark only comes very sporadically and is very weak. (It is the same with two function ignition coils).

I measured the voltage at both the red and orange wire which go to the coil.

Red: 13.? volts
Orange: 0 volts

Is this normal? I thought orange and red should both be at battery voltage.

If this is the case and my CDI is connected properly, what does it mean? Is the CDI box bad?

Best,
Adam

 

[pamcopete]

xs650newb,

(It's Transistor Controlled Ignition, TCI, not Capacitor Discharge Ignition, CDI)

Not necessarily. The red wire will always be close to battery voltage if the ign switch and kill switch are on. The orange wire gets an alternating ground / battery from the TCI box as the transistor in the box provides a ground / open in response to the magnet on the flywheel. Just like a set of points opening and closing, so you probably just caught it when it was on.

However, having said all that, the TCI box will also time out if the engine is not running, so the 0 Volts you see should go away in a few seconds if the engine is not running. You should also see an alternating 0 Volts / 12 Volts on the orange wire as you turn the engine over. If you do not see either of these conditions, then the TCI box may be toast. Search the forum for threads on repairing the TCI box. Some people have had good luck in doing so.

 

[xs650newb]

Thanks Pamcopete.

My wiring is correct. My coil is good (tried two different coils), so my TCI is suspect.

If it is, I am just going to order your system.

Adam