I just did all the suspension linkage bolts and bearings on my Kawasaki with valvoline synpower grease.
My recommendations for grease even on motorcycles are:
Mystic JT6 hi temp grease (wal-mart has it)
Valvoline Synpower Grease (napa and many other auto parts stores have this)
CRC new generation disc brake wheel bearing grease (napa carries)