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SHIPPING UPDATE: Due to high demand, orders are currently processing in 5-7 business days. Need it faster? Contact us to upgrade to expedited shipping! If you’ve found the item elsewhere or can’t wait, no problem—we completely understand. Just reach out to us, and we’ll cancel your order. Thanks for your patience and support! BRAPPPPPPPPPP!

Honda TRX400EX

Honda 400EX Rebuild Kits, Pistons, and Parts

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TRX400EX 400EX 400X XR400 88mm Big Bore Cylinder JE Piston & Gaskets Rebuild Kit

BPRATV

1043-2, M2002, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-...

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TRX 400EX 400X 88mm Big Bore Cylinder 13:1 JE Piston Cometic Top End Rebuild Kit

BPRATV

1043-2, M2002, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-...

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TRX 400EX 400X XR400 88mm Big Bore Cylinder 13:1 JE Piston & Gaskets Rebuild Kit

BPRATV

1043-2, M2002, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-...

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$888.89
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TRX400EX 400EX Assembled Cylinder Head Stage 2 Hot Cams Chain & 87 88 89 Cometic

BPRATV

14711-KCY-670, 14721-KCY-670 14411-KCY-670, 14431-KCY-670, 14445-KF0-000 14446-KF0-000, 14751-KCY-670, 14761-KG0-003 14451-MBV-000, 14781-HA0-770, ...

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400EX 400X XR400R Cylinder Head Stage 2 Hot Cams WISECO Chain Stock Cometic Kit

BPRATV

14711-KCY-670, 14721-KCY-670 14411-KCY-670, 14431-KCY-670, 14445-KF0-000 14446-KF0-000, 14751-KCY-670, 14761-KG0-003 14451-MBV-000, 14781-HA0-770, ...

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$419.88
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Honda TRX400EX TRX 400EX Assembled Cylinder Head Stage 2 Camshaft Chain Bearings

BPRATV

14711-KCY-670, 14721-KCY-670 14411-KCY-670, 14431-KCY-670, 14445-KF0-000 14446-KF0-000, 14751-KCY-670, 14761-KG0-003 14451-MBV-000, 14781-HA0-770, ...

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Honda TRX 400EX X Top End Rebuild Repair Kit CP Carrillo Piston Gaskets Cylinder

BPRATV

Complete Standard Bore Top End Rebuild Kit!Honda TRX400EX & TRX400X Years 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012...

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05+ 400EX 400X Big Bore Stroker Complete 465cc Rebuilt Motor Engine Rebuild Kit

BPRATV

4240,CBK0037,CBK0163,808894,TBK0012,K014, 12100-KCY-670, 4606M08500, C7826, 71016-412191-KCY-673, 13011-KCY-670, 90601-KA5-00013103-KCY-670, 13111-...

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$469.99
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$398.88
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TRX 400EX TRX400EX 400X 88mm 88 426cc Big Bore Cylinder 10:1 Top End Rebuild Kit

BPRATV

1043-2, M2008, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-...

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$29.74
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400EX 400X Valve Spring Seats Base Washers Steel Copper Wave Washer Head Rebuild

BPRATV

WORKS ON ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS!If you bought a so-called "complete" head rebuild kit online unless it was from us it is ...

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$34.99
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$668.89
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Honda 400EX 400X 87mm 416cc 12.5:1 CP Piston Big Bore Cylinder Stage 2 Hot Cams

BPRATV

1043-2, M2008, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670, 13...

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$926.28
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$799.99
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Honda 400EX 400X Cylinder Head Assembly Top End Rebuild Kit Valves Rocker Arms

BPRATV

Complete Top End Rebuild Kit with Head NEW after market 85mm, stock bore cylinder Wiseco or Wossner forged piston** Nitrite coated piston rings Chr...

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$369.99
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$288.89
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Honda TRX400EX XR 400X Top End Rebuild Repair Kit Wiseco Piston Gaskets Cylinder

BPRATV

12100-KCY-670, 4606M08500, C7825, 12191-KCY-673, 13011-KCY-670, 90601-KA5-000, 13103-KCY-670, 13111-KCY-670, 12251-HN1-003, PK1031Complete Standard...

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$500.49
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$323.89
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Honda 400EX 400X XR400 Top End Rebuild Kit CP 10:1 Piston Gaskets Cylinder NGK🔥

BPRATV

Complete 85mm Stock / Standard Bore Top End Rebuild Kit With CP Carrillo Piston and Cometic GasketsThe best rebuild kit on the market should have a...

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Honda TRX400EX 400EX TITANIUM Cylinder Head Valve Cover Bolts & EXHAUST STUD KIT

BPRATV

BPRATV - The Original Trailblazer for Titanium Hardware in the ATV Industry. Fits Honda TRX 400EX 400X XR400 All Years!Race to the finish line with...

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$151.99
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$768.99
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99-04 400EX 400 EX 87mm BPR Simple Rebuild Kit CP Piston Complete Gaskets Seals

BPRATV

Honda TRX 400EX 400X Simple Rebuild Kit (Big Bore 87mm) We've heard your feedback! Some of our kits are Too Complete. We mean it when we say no one...

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99-04 400EX 400 EX 89mm BPR Simple Rebuild Kit CP Piston Complete Gaskets Seals

BPRATV

Honda TRX 400EX 400X Simple Rebuild Kit (Big Bore 89mm) We've heard your feedback! Some of our kits are Too Complete. We mean it when we say no one...

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$999.99
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$718.99
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99-04 400EX 400 EX 87mm Simple Rebuild Kit Wossner Piston Complete Gaskets Seals

BPRATV

Honda TRX 400EX 400X Simple Rebuild Kit (Big Bore 87mm) We've heard your feedback! Some of our kits are Too Complete. We mean it when we say no one...

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TRX400EX TRX 400EX Big Bore Kit Stage 2 Hotcam 87mm +2 Cylinder Hotcams Camshaft

BPRATV

FITS ALL HONDA TRX400EX, 400X, AND XR400R MODELS AND YEARSAfter market 87mm cylinder  Wiseco CP or JE forged piston**  Hi temp piston rings  Chrome...

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$599.99
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get best honda 400ex top end replacement near me
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BPRATV TRX400EX TRX 400EX Cylinder Wiseco Piston Stock Bore Top End Rebuild Kit

BPRATV

12100-KCY-670, 12191-KCY-672, 13011-KCY-670, 13101-KCY-670, 90601-KA5-000, 13111-KCY-670, 12100-HN1-A70, 12191-KCY-672, 12251-HN1-003, 12391-KCY-67...

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TRX400EX TRX 400EX Big Bore 89m 440 Wiseco 12.5:1 Top End Rebuild Kit Head Stud

BPRATV

BIG BORE TOP END POWER!  SE HABLA ESPANOL! FITS ALL HONDA TRX400EX, 400X, AND XR400R MODELS AND YEARS BOLT ON RELIABLE BIG BORE POWER! Kit inclu...

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TRX400EX TRX 400EX Stage 2 Hotcam Hot Cam Valves Springs Rockers Head Rebuild

BPRATV

FITS ALL HONDA TRX400EX TRX400X AND XR400R YEARS AND MODELS   COMPLETE PERFORMANCE HEAD REBUILD KIT! Stage 2 Hotcam Complete valve train head reb...

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TRX400EX TRX 400EX 88mm Big Bore Stage 2 Cam Kibblewhite Valves 426 Top End Kit

BPRATV

1043-2, M2008, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-...

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TRX 400EX 400X Webcam Web Cam Kibblewhite Valves Valve Springs Head Redo Kit

BPRATV

FITS ALL HONDA TRX400EX, XR400, AND 400X YEARS AND MODELS!  Webcam custom grind high performance camshaft Kibblewhite race valve spring kit Ki...

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$692.99
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TRX 400EX 400X XR 416 Big Bore Kit 87 mil Cylinder +2 Complete Top End Rebuild

BPRATV

Compatible Vehicles Submodel Year Make Model TRX400EX 2x4 2008 Honda Sportrax 400 TRX400EX 2x4 2007 Honda Sportrax 400 TRX400EX 2x4 2...

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$473.54
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*TRX 400EX 400X Hotrods Crank Bearings Hot Rods Rod Crankshaft Main Bearing Kit

BPRATV

WORKS ON ALL HONDA 400EX AND 400X MODELS AND YEARS - BUY IN BULK AND SAVE $$ Hotrods OEM replacement crankshaft with gear Connecting rod, rod be...

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TRX 400EX 400X Assembled Head Assembly Stage 2 Hot Cam Chain Hotcam Camshaft Kit

BPRATV

FITS ALL XR400R TRX400EX and TRX400X MODELS New aftermarket cylinder head and valve cover Stage 2 Hotcams camshaft HD cam chain conversion SKF cam...

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$999.99
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$1,154.95
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$72.99
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TRX 400EX 400X Stock Bore Piston Aftermarket 10:1 Standard 85mm Head Gasket Kit

BPRATV

FITS ALL HONDA 400EX 400X XR400R YEARS AND MODELS!! BUY IN BULK AND SAVE!! Standard 85mm 10:1 piston Piston rings Wristpin Circlips Top end gaske...

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$1,154.95
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TRX 400EX 400X Cylinder Head Valve Cover Complete Rebuild Kit Stage 1 Hotcam

BPRATV

FITS ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS - THE ONLY TRULY COMPLETE REBUILD KIT ONLINE All parts are aftermarket Cylinder head Valve ...

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TRX 400EX 400X Top End Rebuild Kit Stock Bore Cylinder Piston 85mm Assembly Part

BPRATV

1043-2, M2002, M2003, M2001,4606M08700,12100-KCY-670, 4606M08500, C7826, 71016-4, 12191-KCY-673, 30-33750, 13011-KCY-670, 90601-KA5-000, 13103-KCY-...

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TRX 400EX 400X Big Bore 89mm 10:1 Piston Kit Top End Gasket Cometic Head Gasket

BPRATV

FITS ALL HONDA 400EX 400X XR400R YEARS AND MODELS!! Standard Aftermarket 89mm 10:1 piston Piston rings Wristpin Circlips Top end gasket kit COMETIC...

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400EX Ported Cylinder Head Porting Assembled +1 Valves Kibblewhite 1mm Valve Kit

BPRATV

Brand new aftermarket cylinder head and valve cover Full race port and polish - intake, exhaust, combustion chamber Valve guides cut Pocket port ...

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400EX Ported Cylinder Head Assembly Stage 2 Hotcam Kibblewhite Studs Complete

BPRATV

Brand new aftermarket cylinder head and valve cover Full race port and polish - intake, exhaust, combustion chamber Valve guides cut Complete ass...

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99-04 TRX 400EX 89mm Rebuild Kit Top Bottom Big Bore Motor Engine Assembly 440c

BPRATV

WORKS ON ALL '99-04 HONDA 400EX MODELS Aftermarket 89mm big bore cylinder 89mm big bore Wiseco JE or CP forged piston* Nitrite coated piston rings ...

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$1,299.99
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Best 400EX 400X XR400R Black Billet Cam Chain Tensioner Heavy Duty Timing Chain

BPRATV

FITS ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS Aftermarket heavy duty timing chain upgrade Black billet cam chain tensioner Chain tensioner...

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99-04 TRX 400EX 88mm Rebuild Kit Top Bottom Big Bore Motor Engine Assembly 426c

BPRATV

WORKS ON ALL '99-04 HONDA 400EX MODELS Aftermarket 88mm big bore cylinder 88mm big bore Wiseco JE or CP forged piston* Nitrite coated piston rings ...

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$1,099.99 - $1,099.99
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