Bel Ray H1R Racing Synthetic Ester 2T Motor Oil Bel Ray H1R Racing Synthetic Ester 2T Motor Oil is formulated for all power valve 2-stroke engines. Advanced 100 synthetic ester base oils cling to metal, preventing wear in all 2-stroke applications. Clean burning to prevent carbon build-up in combustion chambers and valves. Not suitable for methanol fuel. 2013 Cik-Fia Certified for use in high performance racing kart applications.