Need some help please .. I have a 1993 kx250 the issue is the big bore kit and needs some new rings on it.. the piston is in great shape with no markings on it or cyl walls the problem is the rings are bad and can't find anything nowhere, .. the piston says on the top 73.95mm . from what i been reading is a big bore kit. another number on top of piston says 9050 right over the 73.95mm on the backside by pin it says 2310 if anyone out there has anything that would help with any info would be great. thank you so much