im currently rebuilding my 02 yz426 becuase my rod bearing siezed on me.(just sent my crank out to mr. crankshaft) i got a few questions first; has anyone used these hot rods bearings for the main crankshaft bearings http://cgi.ebay.com/ebaymotors/YAMAHA-YZ426F-YZ426-CRANKSHAFT-CRANK-BEARINGS-00-02-_W0QQcmdZViewItemQQhashZitem35b08292f5QQitemZ230594614005QQptZMotorcyclesQ5fPartsQ5fAccessories found this one on ebay for a set for 60$ compared to 50$ a piece for the oem's. curious what others have done or if these are one of those parts you should go oem. next question ; all the bearings appear to be in good shape and turn smoothly. but i know you guys are going to tell me to replace them anyways sence im in there. does anyone have a link to someone that sells all the bearings as a kit. or should i just go on bikebandit and buy the oem bearings one by one. aftermarket one by one? next question; i keep reading that i should replace my timing chain while im in there as well. do these chains have short lives or is it just a paranoid preventive maintenace thing? my chain moves smooth/free and is very tight when installed should i replace it still? would these be considered a interference head like on cars if it was to break? also whats normal wear for the oil pumps? there is cirlcular grooves on the metal star and housing. but they still spin freely already got my cylinder cleaned up and will be ordering a new piston kit as well. thanks for reading and looking forward to reading any input.