I also experienced the check engine light being on. After installing the fuel controller and exhaust system.
This was done at 29 miles.
Due to life in general. Riding the bike for an extented length wasn't an option. The only exceptions being. A few startups until the engine warmed, then a lap or two around the lawn... Until yesterday!
The weather was a bit windy, but it didn't deter me.
I rode the bike on a errands run. Making several stops. My odometer reading was at 55 miles when I noticed the yellow check engine light was no longer lit! Whew! The bike runs great & the top speed I achieved was only 51mph. But, I never was *** nor did I hit the limiter.
So, like MNNTHBX wrote. Ride it and it will correct itself.
Thanks to all of you here that's helped me on my build.
Happy Thanksgiving to everybody & Cheers! Ride safe! And,call your loved ones - tell em so.