models with the 4453 upper tree bolt & 4350A clamping screw system)

656" / Dome -57cc

rear 903397

12-16 Dyna FLD Switchback

2012-up) mixture screw (MCS 940521) o-ring type mixture screw

S&S, 88" to 97" big bore cylinder & piston kit. Black Supertrapp Universal models with the 4453 upperDescription Black powder coated cylinders. No need to bore out the cases. With 3. 927" bore S&S feels this is the largest bore possible that can be safely used with stock bore crankcase spigots. Fits stock 4" stroke 88" Big Twin models and increases capacity to 97". 9. 7: 1 CR with stock 85cc cylinder heads, 10. 3: 1 CR with S&S 79cc heads. The forged pistons requires no flywheel re balancing and valve pockets are enlarged to acommodate oversize