I was wondering the same myself Bonnar_Bloke, I thought it must have been a problem before. I�m thinking about doing the same to one of my powertorque mowers as sometimes my wintergreen seems a little dry in the few days after mowing. I�m sure it�s the poor soil it�s growing in, but it can�t hurt to try and see if there is any noticeable difference. Not scientific I know, but I�m sure 2 stroke exhaust isn�t great for fresh cut grass