BC9951 – Yamaha YXZ/998 CNC Cylinder Head – Big Port 31mm/27mm Valves

Use pulldowns above to build out your head.

The BC core exchange program works three ways:

1) Buy one of BC’s new heads outright, no exchange.

2) Send a new head in for even exchange for one of BC’s new in-stock heads. Check with BC for availability.

3) Send a used head in, receive that same head back + $150 for complete inspection prior to machine work.

BC only accepts new, never-been ran Yamaha heads (#2HC-11101-09-00) cylinder heads as new core exchanges. BC uses only new heads for all new even exchanges. All heads come with BC bronze valve guides installed as well as STD Stainless Steel intake/+1mm Inconel exhaust valves. Any valve springs, retainers, keepers, cams or ARP head studs are sold separately in the pulldown menus.

If sending a new head, allow 1 week for inspection before new CNC head ships. If sending a used head, allow 4-8 weeks for that head to be ported. No exchanges on used heads. Send heads for servicing here:

BrianCrower, Inc, 161 So Marshall Ave, El Cajon CA 92020