Rebuilding a 93 fxr from ground up, got the engine in and wired up, but have a weak spark, ignition is good, coils, wires plugs, batt new, wiring is correct, but not to sure about the voe switch.
Was wondering what could be giving me week spark.
Starting at the ground, where should i look next.

 

Well, you need a good, fully charged battery.
How are you determining that the spark is weak?

 

batt is new and fully charged, i've been grounding the plug off the head, seeing some faint spark. but nothing close to what i should be getting.

 

If you have an owners manual, maybe to a coil check.

 

Coil is brand new.And getting the correct amps at the contact posts.

 

new coil doesn't mean good coil

 

Yep, you could try the old coil.

 

coil is fine, just ran it on another bike.

 

Battery issues come into play when you can confirm a good battery with a solid deep charge but may have corroded / faulty / loose connections in the circuit.

You may need plug wires, or fresh plugs.

If the voltage to the coil is correct, even under the load of the motor starter running, and you only get a weak spark with fresh wires and plugs, then you have to go "upstream" from the coil.

You have a cam sensor on that EVO, and a stock factory ignition module that send the "spark signal" to the coil. If they are not functioning correctly the duration of the spark, or coil charging, could be effected and only create a weak spark.

Both are tough to test unless they completely fail. Often they falter under heated conditions. Check the supply voltages.

 

I was also thing maybe a bad ground somewhere.