I was having a problem with my Whizzer NE-5 M/B misfiring every once in a while. At Idle, mid range and full throttle but not always only once in a while.
Sometimes it would start missing at idle and sounded like the fuel air mix screw was off a little. (too rich or too lean) Adjusting the A/F screw did nothing.
Next I cleaned the Carb That seemed to fix it but the misfire soon returned.
So having a 4 stroke I checked the valve lash. The lash was OK. I ruled out valve float Because it acted up at idle besides full throttle.
I check the S/P and wire Check for a compression leak Check the trigger P/U and wire to the CDI Checked wires to coil
The CDI is in question now. It's old and I figure it must be weak and it's time for a new one. I put in a new 5 pin AC CDI.
The bike ruins great no missing and I think I have fixed the problem only to have the bike start acting up a few hundred miles later.
I'm thinking the new CDI is failing, but why so soon? I decide to start wiggling wires and the wiring harness to see if I can duplicate the problem. I can
I chase the problem to the CDI plug. It turns out one of the contact pin connectors was dirty, loose and hardly making contact. So I took all 5 pin connectors out of the plug cleaned and tightened up the little slots where they slide together. put everything back together, Now my bike runs great again NO missing.
I tell this story because it has taken me 5 weeks to figure out a plug contact was dirty and kinda loose.
While working on the bike or just riding the bike I would bump the wires and plug from the CDI by accident and that was making it better or worse without me knowing it.
The 5 pin CDI plug looks good and the wires can't be pulled out. Looking at the contact pins and connectors from inside the plug they looked good too. But one contact pin connector inside was dirty and loose making a weak connection. A Phantom Short
Sometimes it would start missing at idle and sounded like the fuel air mix screw was off a little. (too rich or too lean) Adjusting the A/F screw did nothing.
Next I cleaned the Carb That seemed to fix it but the misfire soon returned.
So having a 4 stroke I checked the valve lash. The lash was OK. I ruled out valve float Because it acted up at idle besides full throttle.
I check the S/P and wire Check for a compression leak Check the trigger P/U and wire to the CDI Checked wires to coil
The CDI is in question now. It's old and I figure it must be weak and it's time for a new one. I put in a new 5 pin AC CDI.
The bike ruins great no missing and I think I have fixed the problem only to have the bike start acting up a few hundred miles later.
I'm thinking the new CDI is failing, but why so soon? I decide to start wiggling wires and the wiring harness to see if I can duplicate the problem. I can
I chase the problem to the CDI plug. It turns out one of the contact pin connectors was dirty, loose and hardly making contact. So I took all 5 pin connectors out of the plug cleaned and tightened up the little slots where they slide together. put everything back together, Now my bike runs great again NO missing.
I tell this story because it has taken me 5 weeks to figure out a plug contact was dirty and kinda loose.
While working on the bike or just riding the bike I would bump the wires and plug from the CDI by accident and that was making it better or worse without me knowing it.
The 5 pin CDI plug looks good and the wires can't be pulled out. Looking at the contact pins and connectors from inside the plug they looked good too. But one contact pin connector inside was dirty and loose making a weak connection. A Phantom Short
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