1. M4 exhaust for 2021 MT-09
This exhaust is awesome . The sound is amazing. The fitment is spot on. However with all New products there is bound to be issues. And these are what I found. When taking off exhaust the radiator support bracket gets in the way. However with proper tools this is not an issue. The only other issue I found is the 02 sensor extension. I feel that the extension could be a bit longer m. This will allow owner to run o2 sensor wire Connection to a More hidden location. Other than that I think this system is worth every penny!