I lost compression on my 230. I pulled cylinder apart and noticed two rings on the piston. I also found a video tutorial on a SRM 225 (not 230) that shows ONE ring. Mine has two! Two vendor online parts stores only list one ring part number. Yet, their schematic shows two rings. Does my SRM 230 require 2 rings of the same part number? Or, are they unique? I am used to rebuilding four cycle motors that have specific and unique rings on each piston. Also, does the cylinder wall require honing before reassembling?????