Skip to content
NOTICE: DUE TO HIGH ORDER VOLUME, CURRENT HANDLING TIME IS 5-7 BUSINESS DAYS. OUR TEAM IS WORKING HARD TO PROCESS YOUR ORDERS AS QUICKLY AS POSSIBLE. WE TRULY APPRECIATE YOUR PATIENCE AND UNDERSTANDING. 🙏
NOTICE: DUE TO HIGH ORDER VOLUME, CURRENT HANDLING TIME IS 5-7 BUSINESS DAYS. OUR TEAM IS WORKING HARD TO PROCESS YOUR ORDERS AS QUICKLY AS POSSIBLE. WE TRULY APPRECIATE YOUR PATIENCE AND UNDERSTANDING. 🙏
400EX 400X 89mm Hi Comp Big Bore Kit Race Gas 12.5:1 Piston +4 Rebuild 440cc Kit

400EX 400X 89mm Hi Comp Big Bore Kit Race Gas 12.5:1 Piston +4 Rebuild 440cc Kit

by BPRATV
Save 18% Save 18%
$461.99
$461.99 - $461.99
$461.99
$379.98
$379.98 - $379.98
$379.98

M2033,4667M08900,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670, 13111-KCY-670, 12251-HN1-003, 12209-KL4-005, C7825, 808894, 822278, 4040, 4606M08700, C7826, H0402027S, 4606M08800, 4667M08900, 808829, M2033, 8604DA


  • NEW 89mm big bore cylinder
  • 89mm Wiseco 12.5:1 big bore forged piston
  • Nitrite-coated piston rings
  • Chrome wrist pin
  • Circlips
  • Cometic big bore top-end gasket kit
  • Cometic MLS head gasket
  • Talon TITANIUM cylinder head stud kit - LIFETIME WARRANTY*!
  • NGK spark plug
  • HD cam chain conversion
  • Piston uses pump or race gas
  • Works on all Honda 400EX, 400X, and XR400R models and years
  • 1-year warranty*
This is a bolt-on kit that requires no machining of any kind.  Runs on pump or race gas.  Everything is new in the original packaging and the manufacturer's warranties apply***.

Compare products

{"one"=>"Select 2 or 3 items to compare", "other"=>"{{ count }} of 3 items selected"}

Select first item to compare

Select second item to compare

Select third item to compare

Compare