on a BX:Been doing it since day one,someone told me DON'T DO THAT!!!!! will this hurt my bx??? high range 1600-2200 rpm,takes me 3.5 hours to mow
low range, 3000+ RPM -- first, you'll get a better cut (more vacuum to stand the grass up straight, and more blade tip speed to sever the grass). second, the tractor makes a ton more power/torque at 3000+ RPM compared to 1600 RPM. the MMM is designed for 1000 RPM midPTO input; depending on which BX model you have you will need to run the engine above 3000 RPM to achieve that. consult your manual about what engine speed corresponds to 1000 RPM midPTO speed.
the way you are doing it with the throttle set at 1600-2200 RPM is not beneficial to anything; neither the tractor nor the grass is better off for it. you are not going to hurt your BX by increasing mowing RPMs; the Kubota diesel engines used in the BX series are designed for thousands of hours of continuous use at full rated output power. you will run out of the desire to cut grass a long time before running out of tractor.
wrooster