SMJ Kabuto Engines SMJ1356: SMJ Kabuto R21 ENGINE #SMJ1356B: SMJ Kabuto R21 ENGINE (Pre-Broken in) SMJ1155 : SMJ Kabuto 21XB2 ENGINE POWER SPEC ’19 (Pre-Wrapping) SMJ Kabuto R21 Model ’18 ENGINE (Pre-broken in) SMJ1115: SMJ Kabuto R21 Engine (Pre-Broken in)