2022 CT125 4k miles Misfires Looses Power at WOT Solution.

What was a rare annoyance became a persistent issue that I was reluctant to address while the bike was under issue. At full throttle the bike would miss to the point where anything past 3/4 throttle was inaccessible in cold weather especially. Yesterday I checked the air filter and it was clean. I then looked at the sparkplug and it was practically finger tight. My suspicion is all the wet weather riding caused corrosion and loosened the plug. Torqued the plug back down and I am now happily enjoying those blistering speeds these bikes are known for. I hope this post helps someone in the future.

Glad you caught it before the air leak caused more damage from running lean. I would recommend doing a thorough inspection of the threads on the head to make sure they are not damaged.

weather had nothing to do with it being loose, it was never tightened down . glad you found it, really glad it didn't wiggle loose enough to damage the threads in the head.

One more common cause of misfire in Cold Temps is a low charge on a battery or Bad Battery.

First indication you'll get on a low Battery before it misfires is the ABS Light will come on(if so equipped with ABS).

Much to my dismay I have to revisit this thread/issue. When I changed the sparkplug the issue went away for a month but has increased in frequency to the point I can't depend on the bike to make it into to town safely at its reduced speed. The Problem is dramatically worse in cooler/cold weather 75F> I now have a video of it misfiring. I am going to proceed to change the fuel filter and try to pull codes. I will follow up on this thread with a definative solution.

I hate to be the one to mention it but you may have a damaged (cracked) head. Not on Motorcycles but on engines in cars I've seen a head develop a hairline crack and cause intermittent rough running periodically. The fact that previously your Spark Plug was so loose could be another indicator.

an easy way to check is to pour some rubbing alcohol on the suspected area and watch it evaporate. IF there's a crack, as the surface dries out, the crack will present itself as the alcohol wont be able to evaporate as fast and it will locate it really fast. However, i doubt thats the case here. Id start looking at the coil connections, make sure they arent loose.

I proceeded to run a compression test then a fuel pressure test. Lil' red passed in flying colors. I followed by looking at the electrical (my weakest jutso). I removed the plastic work and took a look first at the coil and electrical connectors. I then took aim at the ground cable and up to the battery.....
This is how the dealer delivered my new bike for a modest 500 assembly fee. Why does a kickstart bike need a battery tender anyways wtf? I Discarded the battery tender pig ears and retorqued the battery terminals. Bike is now back to cruising at 55 with very smooth linear acceleration. I m not sure if the problem was a poor connection or resetting the ecm when the terminals got reinstalled. I will report back after a few hundred miles to verify the repair.

It doesn't need a battery tender, that's something that some dealers add. If you already have a maintainer that can plug into it, then it's a nice perk, if not, then it sometimes drums up additional business for them selling battery maintainers. If you store the bike long term it can be useful. The battery will slowly self discharge, and if it drops below a healthy voltage it can damage the battery, and potentially also damage the regulator/rectifier when you run the bike again and it struggles to charge a drained or failed battery.

Nice work tracking it down. Hopefully that's all it was and you've got it fixed for free.

nice. you can reinstall and add a 5mm washer to keep it from moving around under the bolt but over the tender eyelet.

I have one on mine, but its so i can hook a usb adapter to it and charge stuff if its in the rack. Hopefully that was it and its good to go.

Put another 500 miles on the bike and can now confirm the fix. "lil Red"Now sitting just under 6k. Bike is running perfect. Noticed the bike will now start with a lazy 1/2 kick versus a deliberate 1 or 2 kicks on a cold day. These bikes love a strong spark.