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Honda TRX400EX

Honda 400EX Rebuild Kits, Pistons, and Parts

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TRX 400EX 400X Cylinder Head Valve Cover Complete Rebuild Kit Valves Rocker Arms

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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400EX XR400R Titanium Cylinder Studs Head Studs Crankcase Cylinder Head Stud Kit

BPRATV

BPRATV - The Original Trailblazer for Titanium Hardware in the ATV Industry.  Fits Honda TRX400EX & XR400X All Years & Models Kit includ...

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Honda 400EX 400X 87mm +2 Big Bore Kit Stage 3 Hotcam 416cc Top End Rebuild Kit

BPRATV

Works on all Honda 400EX, 400X, and XR400R models and years 87mm heavy duty big bore cylinder 87mm big bore Wiseco or Wossner forged piston Nitri...

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

BPRATV

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-en...

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400EX 400X Stage 1 Hotcam OEM Stock Replace Camshaft Valves Rockers Head Rebuild

Hotcams

FITS ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS - THE ONLY TRULY COMPLETE REBUILD KIT ONLINE All parts are aftermarket Stage 1 Hotcam  SKF ...

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400EX Sportrax Stroker Crank Bearings Hotrods 4 mil +4mm Crankshaft Rod Bearing

BPRATV

WORKS ON ALL HONDA 400EX AND 400X MODELS AND YEARS - BUY IN BULK AND SAVE $$ Hotrods +4mm stroker crankshaft with gear Connecting rod, rod beari...

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Honda 400EX 400X +1 Ported Head Port Porting Kibblewhite 1mm Valves Assembled

BPRATV

FITS ALL HONDA TRX400EX, 400X, AND XR400R MODELS AND YEARSNEW after-market cylinder head and valve cover Full race port and polish Valve guides cut...

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$149.99
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$129.99
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400EX 400X XR400 Kibblewhite Valves Valve Seals Black Diamond Intake Exhaust Kit

Kibblewhite Precision

FITS ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS!! Kibblewhite Black Diamond kit Stainless steel one-piece valve construction MADE IN USA Std ...

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$649.99
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$499.19
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Honda 400EX 400X XR400R Assembled Cylinder Head Stage 2 Camshaft Chain Bearings

BPRATV

Revitalize your Honda TRX400EX, 400X, or XR400R with a powerful new cylinder head and valve train from BPRATV.Key features: Complete assembled cyli...

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$94.99
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$90.10
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TRX400EX 400EX Timing Guides Guide Tensioner Chain Tensioner HOTCAMS Cam Chain

Honda OEM

FITS ALL HONDA 400EX 400X XR400R MODELS AND YEARSAftermarket Cam chain guide - Replaces OEM Part # 14620-KCY-670Aftermarket Cam cam chain tensioner...

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$78.99
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$56.14
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Honda 400EX 86 87 88 89 mm Big Bore Cometic Top End Gasket Kibblewhite RED Seals

Cometic Gaskets

Cometic Complete Top End 89mm Big Bore Gasket KitPart # C7826UPC: 191070011307For 86, 87, 88, 89mm Big Bore & Stroker KitsGREAT FOR 416cc, 426c...

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$269.99
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$216.79
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$216.79

Honda TRX400EX TRX 400EX Kibblewhite Head Intake & Exhaust Valves Seals Springs

Kibblewhite Precision

Breathe new life into your Honda TRX400EX with this complete performance valve upgrade kit from the pros at Kibblewhite.Key Features: Black Diamond...

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$99.99
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$67.89
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Honda TRX400EX TRX 400EX TITANIUM Lug Nut Complete Set Front Rear Kit Set of 16

BPRATV

Stand out from the crowd with the Honda TRX400EX TRX 400EX TITANIUM Lug Nut Complete Set Front Rear Kit Set of 16! This bling-tastic titanium lug n...

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$119.99
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$94.98
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Honda TRX400EX TRX 400EX TITANIUM Cylinder Head Valve Cover Bolts Cam Bolt 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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99-04 TRX400EX TRX 400EX TITANIUM Cylinder Head Valve Cover Bolt Kit Ti Hardware

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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TRX 400EX 400 400X Kibblewhite +1 Valves Springs Complete Valve Head Rebuild Kit

Kibblewhite Precision

Take your Honda 400EX, 400X or XR400R to the next level with this complete valve head rebuild kit from Kibblewhite. This high-performance kit gives...

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$21.99
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$17.09
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99+ Honda TRX400EX TRX 400EX 400X Head Valve Stem Guide Seals Seal Set of 4 Four

Kibblewhite Precision

Boost Your Honda TRX400EX's Performance With KPMI® Red Viton Valve Stem SealsKey Features/Benefits: Made from 100% Viton for maximum heat resistanc...

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$308.30
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$208.03
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$208.03

Honda TRX400EX 400EX 400X 87mm 10.8:1 416cc JE Piston Cometic Gaskets Kit Seals

JE Pistons

JE 87mm 10.8:1 416cc Big Bore Piston Kit & Cometic Top End Gasket SetFits Honda TRX400EX, TRX400X, and XR400Years 1999 2000 2001 2002 2003 2004...

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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 YEARS After market 87mm cylinder  Wiseco CP or JE forged piston**  Hi temp piston rings  Chrom...

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TRX400EX TRX 400EX OEM Cylinder Genuine Honda Original Top End Rebuild Wiseco

BPRATV

FITS ALL HONDA TRX400EX TRX400X AND XR400R YEARS AND MODELS  GENUINE OEM HONDA CYLINDER 10:1 Wiseco forged piston Hi temp piston rings DLC chrome ...

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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 Stage 3 Hotcam Hot Cam Valves Springs Chain Head Rebuild Kit

Hotcams

FITS ALL HONDA TRX400EX TRX400X AND XR400R YEARS AND MODELS   COMPLETE HEAD REBUILD KIT! Stage 3 Hotcam Cam bearings Rocker arms Rocker arm shafts...

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$692.99
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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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$258.50
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$199.49
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Honda 400EX OEM Oil Pump Replacement Rotors K&N Oil Filter Seal Gasket Rebuild

BPRATV

WORKS ON ALL HONDA TRX400EX AND TRX400X MODELS AND YEARS Oil pump Oil pump gear Oil pump seat/gasket K&N oil filter Filter cover o-ring Oil p...

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$258.50
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$199.49
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$199.49
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$449.86 - $449.86
$449.86
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$449.86

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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$449.86 - $449.86
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$999.99
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$999.99
$854.99
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$854.99

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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$699.99
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$598.49
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TRX 400EX 400X Cylinder Head Valve Cover Complete Rebuild Kit Stage 2 Hot Cam

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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$82.99
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$69.34
$69.34 - $69.34
$69.34

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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$849.99
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$849.99
$712.49
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$712.49

TRX 400EX 400X Assembled Head Complete Assembly Valves Rockers Stage 2 Hotcam

BPRATV

FITS ALL HONDA 400EX 400X XR400R MODELS AND YEARS All parts are aftermarket Cylinder head assembly Valve cover assembly Valves, springs, rocker ar...

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$299.99
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$299.99
$227.99
$227.99 - $227.99
$227.99

TRX 400EX 400X Stage 1 Hotcam Hot Cam Camshaft Bearings HD Chain Conversion Kit

BPRATV

FITS ALL HONDA TRX400EX, 400X, AND XR400R MODELS AND YEARS Stage 2 Hotcams camshaft HD timing chain conversion - a thicker, stronger chain that doe...

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$799.99
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$569.99
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$569.99

TRX 400EX 400X Assembled Head Assembly Complete Valves Valve Cover Spring Rocker

BPRATV

WORKS ON ALL HONDA 400EX 400X XR400R MODELS AND YEARS NEW aftermarket cylinder head with valve cover Valve springs Valve spring seats Val...

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$569.99
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$469.36 - $469.36
$469.36
$469.36 - $469.36
$469.36

99-04 TRX 400EX Bottom End Rebuild Kit Hotrods Crank Lower Motor Engine Assembly

BPRATV

FITS ALL '99-04 HONDA 400EX MODELS Hotrods replacement crankshaft with rod assembled SKF heavy duty replacement crank bearings Complete gasket ki...

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$469.36 - $469.36
$469.36
$469.36 - $469.36
$469.36
$1,234.99 - $1,234.99
$1,234.99
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$1,234.99

99-04 400EX Big Bore Stroker Kit 89mm Rebuild Complete Top Bottom 465cc Assembly

BPRATV

FITS ALL '99-04 HONDA TRX400EX MODELS Kit includes: NEW 89mm cylinder CP forged stroker piston Hi temp piston rings DLC chrome wristpin Circlips ...

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$1,234.99 - $1,234.99
$1,234.99
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$1,234.99
$123.49 - $123.49
$123.49
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$123.49

400EX 400X TRULY COMPLETE Head Rebuild Redo Valve Valve Springs Rocker Arm Shaft

BPRATV

FITS ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS - THE ONLY TRULY COMPLETE REBUILD KIT ONLINE Steel intake and exhaust valves Inner and oute...

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$123.49 - $123.49
$123.49
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$123.49
Save $135.00 Save $0.00
$799.99
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$799.99
$664.99
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$664.99

99-04 400EX Sportrax Crank Bottom End Rebuild Crankshaft Motor Engine Assembly

BPRATV

FITS ALL HONDA 400EX 400X AND XR400R MODELS AND YEARS Hotrods or Wiseco crankshaft assembly with rod Complete gasket kit MLS head gasket  Oil seal...

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$799.99
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$1,139.99
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$1,139.99

05+ TRX 400EX 400X 89mm Big Bore Rebuild Kit +4 Complete 440 Stage 2 Hotcam

BPRATV

FITS ALL '05+ TRX400EX and TRX400X MODELS 89mm after market cylinder Wiseco CP or JE 89mm forged piston**  Nitrite coated piston rings Chrome wris...

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$1,139.99
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