Anytime we modify exhaust there may be a difference in emissions. How much? In the US we have federal standards that would likely be followed by state regulations.
In the US emission rules prohibit the modification of exhaust but, the law is obviously hardly followed.
I admit I don't like stock...
This might help. Randy talked about torquing in increments using a pattern. He also found the same torque specification for multiple bikes.
https://www.600riders.com/threads/fsm-error-read-or-engine-damage-may-occur.51784/#post-571716
Interesting. I think if you force the spark but the engine isn't rotating the computer is seeing that it produced a spark but it did not see the CPS signal. It throw the error code for no CPS.
When you do crank the engine and it fails to fire, do you see error 12?
Another thought is maybe...
The cluster has a CPU that processes the data and then drives the LCD. It sounds like they know their business.
Solid state often fails with no magic smoke release.
What error codes do you have? If you're seeing no spark and you're seeing error code 12 you might have a bad CPS. You haven't mentioned 33/34 codes so your coils and ECU switching transistors would be good. The CPS resistance might be okay but that doesn't mean the the unit is sensing magnetic...
I agree about low voltage and the ECU throwing random codes. In post 51 it was stated there was only 1 spark registered. If there were no additional spark events registered during the crank when the battery was healthy it could be the CPS if a 12 was registered.
We're at the chicken or the egg...