They use to make a 89.5mm piston and you could bore and hone your sleeve for your top end build…..not sure they can be found anymore….if not you will need to resleeve and new piston…thats some $ for labor. I might suggest finding a used cylinder for a smaller bore…..
1984 Honda 200M ATC
1985 Honda 200X ATC
1986 Honda 200X ATC
1999 Honda 406EX....11:1, Web Cam / Hardened rockers. Ported. WB CDI. CT Racing header. WB E-Series slip on. Lonestar swinger.
2001 Honda/KTM 520 Hybrid Quad. Its like a 400EX but twice the horsepower.
2014 Artic Cat Wildcat Trail XT