50 lb/ft front and 45 lb/ft rear mount? Or did you find a better setting for your bike?
I finished up with 45ftlbs on the front and 40ftlbs on the rear which although they seem low are still higher than the torque specs for 85 on bikes. I suspect the best torque settings may vary from one bike to another though.
I noticed no effect on handling but leaving that aside I was fully convinced that engine mount torque settings had perceptible effects on perceived vibration levels. My explanation of why this might be was the engine and frame work together as a structure and variations in the torque settings alter the resonant frequency of that structure so the high rev vibration period is diminished or at least moved to a different part of the rev range. In my case it was diminshed and moved up.
Another technique I heard of but never tried was to tighten the engine mounts with the engine running.