Are you talking about polishing between the bolts or cleaning? Maybe some PS21 gel wheel cleaner for cleaning, I am pretty sure its safe for all wheels.
to fullly get them youll probably have to remove each bolt, those are some sick *** wheels but its tough to get around the bolts. if you do end up taking out each bolt just make sure they are torqued back to spec when you reinstall them
i have the similar RM bbs wheels....i find nothing will perform a proper clean between those bolts...so once a year i let the air out and take everyother bolt out and polish, then refit those and take the other bolts out