10-13-2014, 03:32 AM
Standard MA encompasses MA1 and MA2, if memory serves. A couple of new ratings were necessary because the MA standard had too wide a gamut with regard to friction specification. Some newer bikes specify one of MA1 or MA2 (the BMW K1600 comes to mind). Your bike can use a higher specification, but not lower. So if MA is specified, MA, MA1, or MA2 can be used, if MA1 is specified, MA1 or MA2 may be used, and finally, if MA2 is specified, ONLY MA2 may be used.