YX140 Quit on Me Today

[Old Guy Too Many Bikes]

Went for my weekly ride on my 140 powered CT70 today. Flying down a two lane at about 55 when the engine just died, like the key was turned off. Got it home thanks to the wife and the Honda Fit. Motor still has compression, but no spark. Swapped out the coil and plug from my other bike and tested fine. Figure maybe the CDI unit went bad. Ordered a replacement just in case. Does this happen often? Motor has about 4000 trouble free miles. If it's not the CDI unit, what could it be? The pulsar magnetic pickup and the flywheel look good. Maybe the coil wire grounded out somewhere. I never wired the emergency kill switch. Can I hotwire the coil right to the battery to bypass the ignition switch? I know my way around points, but never had any electronic ignition issues or experience. Any help would be appreciated. I also have a YX140 powered CL90, but getting to the CDI means dropping the engine out, but I could swap out most any other part.

 

[MiniBike Mike’s Garage]

I keep one of these handy. Plug the engine, CDI and coil into this simple harness to bypass the main harness in the bike. If still no spark, problem is somewhere in stator plate.

12v simple harness, CDI, coil, etc
https://amzn.to/3Wto1jZ

 

[OLD CT]

My money is on a fried ignition stator coil. 27 bucks + tax on amazon.

 

[Old Guy Too Many Bikes]

I keep one of these handy. Plug the engine, CDI and coil into this simple harness to bypass the main harness in the bike. If still no spark, problem is somewhere in stator plate.

12v simple harness, CDI, coil, etc
https://amzn.to/3Wto1jZ

Ordered one today, thanks

 

[Old Guy Too Many Bikes]

My money is on a fried ignition stator coil. 27 bucks + tax on amazon

My money is on a fried ignition stator coil. 27 bucks + tax on amazon.

If it's fried, will there be any physical evidence?

 

[OLD CT]

Not always.

 

[Old Guy Too Many Bikes]

Thanks for all the help and advice everyone. Turns out it was a CDI box gone bad. The one I ordered from ebay for $8 won't be here til Wed, but the 12v harness kit that MIni Bike Mike suggested from Amazon got here today and I only ordered it Fri night. Can't believe you get a coil, plug wire, plug, CDI unit, kill switch and ignition switch with keys for $18 shipped. Bike's back on the road and I have plenty of spares for next time.