Saya pakai motor lc, block uma racing 62mm lc. Block beli second piston saya pakai cardinal. Piston ring dah tukar dua kali still sama juga minyak hitam masuk ruang chamber tu yang pelik. Ada org kata block uma ni kena pakai piston uma juga baru dia ok. Tapi tulah piston uma sebiji baru aja 300 lebih saya pakai piston cardinal dia tak fit betul dengan block. Tu yg bertanya dalam ni sapa2 yg ada pakai piston selain uma yg okey bila pakai kat block ni huhu