NU50M-Spark Killer!! Please help!!!

Ok guys hello and please help!! Ive got a Urban Express 50Um-Electric start with NO SPARK!!!! I have replaced everything..new coil, NOS stator, plug, ignition switch and CDI. I still have no spark. I have checked continuity from ignition switch wires to the cdi, redone all grounds I can find new + and - battery terminals...everything. Everything else on the bike works, lights and horn and starter. My 12 v test light comes on when checking voltage to the black/red wire to the cdi and coming off the stator. My trigger wire has continuity to the coil. I have 2 other cdi's that came with the bike as well, no difference. I guess that's why the PO sold it. What am I missing here???

Re: NU50M-Spark Killer!! Please help!!!

Have you replaced the muffler? Maybe you need a new muffler bearing.http://kalecoauto.com/index.php?main_page=product_info&products_id=48

Re: NU50M-Spark Killer!! Please help!!!

Just had a thought after reading about how CDI's are wired on these mopeds and scooters in general. The Black/white wire going to the CDI is the kill wire?? right What if that is grounded or wired wrong some where else on the bike from the PO...that would kill my spark...Right?? so if I cut that wire temporarily going to the cdi, there would be no way for the cdi to kill the spark..right???

Re: NU50M-Spark Killer!! Please help!!!

Right. The kill wire is grounded to kill the bike, disconnect it and there will be no way to shut the bike off. Both the kill switch and the ignition are tapped into the same line leading from the cdi. The cdi power does make a loop through the battery plug and also through the ignition switch plug, both are safety measures to be sure that the bike will not run while the battery power is not connected, which will cause the lights to blow (the NU50M is the only one to have a regulator though so it's ok). So if the battery plug is not connected or the ignition switch is disconnected the bike will not start.

Re: NU50M-Spark Killer!! Please help!!!

OK so I cut the kill wire going to the CDI to rule out that, no change! Still no spark. I checked my AC voltage from the new stator, it is putting out about 65-75 Volts on the high end and about 3 volts from the blue/yellow trigger wire. That's all normal. Only other thing I can think of is my new coil is bad?? Im going to pull it and put it on another bike to test it...What else could it be???

Re: NU50M-Spark Killer!! Please help!!!

I once had an NQ50 Spree which would not spark. After repeatedly checking everything, I found a wiring error. The cdi plugged into a plastic multiwire receptacle block (5 wires maybe). It turns out that 2 of the wires were in the wrong locations (another owner with a running Spree checked the wire locations for me) . I swapped the positions of these wires and got spark. Long shot but worth a check.

Re: NU50M-Spark Killer!! Please help!!!

Still not running!>?!?!? Ive replaced everything on the bike....

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