XScream custom billet 7 port power valve cylinder featuring 2 auxiliary exhaust ports. This +10mm stroker amateur competition short block uses 85mm pistons for 885cc displacement (1 over bore remaining to 85.5mm). 

Short Block Includes: 

  • X Scream Custom billet 7 port power valve cylinder 
  • XScream Billet Head & Domes 
  • Wiseco Pistons 
  • Modified Yamaha 62T cases - Includes XScream epoxy and finger port work, reinforcing front seal area with epoxy, installing a second pulse line fitting, CNC work to match the top case to larger transfer ports on our billet power valve cylinder and boring the cases to accept the +10mm stroker crank. 
  • 78mm Billet Stroker Crankshaft (+10mm) 

- Requires Boyesen RAD Valve intake, XScream XS900 Custom Intake or a Riva reed spacer 

- Also available as top end kit 


Please note: Shipping is not included, Please contact us for a shipping quote.

XS900RR Short Block