[Thereaper1990]

I have a 2017 honda rancher 420 2x4 sra and I'm wanting to change the muffler out but I can't spend the money for an aftermarket system and I've got a muffler picked out but I need a way to bypass or fool my o2 sensor

 

[SamUK]

You’ll find everything you need here....

https://www.hmfracing.com/tech/2014/07/how-does-the-optimizer-work