i have a kawasaki gpx250. i plan on getting a rack. do all racks fit? can i just buy any used rack off ebay? specifically im thinking of this http://cgi.ebay.com.au/UNIVERSAL-MO...orcycle_Parts_Accessories?hash=item20b06349c3 its for a 1984 kawasaki gpz 1100, does it mean it might be too big for my bike?