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Cylinder Head Service Kit, 0.440" Lift, Honda®, CRF™ 450X, 2005-2017

Cylinder Head Service Kit, 0.440" Lift, Honda®, CRF™ 450X, 2005-2017


Regular price $412.17 USD
Regular price $412.17 USD Sale price $412.17 USD
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California Prop 65

KPMI® is proud to introduce full CYLINDER HEAD SERVICE KITS. These kits contain all items to completely refresh and upgrade cylinder heads for popular Dirt / MX and Side x Side models with KPMI’s top quality racing valvetrain components.


  • Save time money on your next cylinder head rebuild
  • One package, everything you need for factory recommended valvetrain service
  • Double your service life over OEM using KPMI® Valvetrain products
  • Kitted with value added savings

Kit Includes:

  • Dual Spring Titanium Retainer Spring Kit, Which Allows for 0.440" Valve Lift
  • Top End Gasket Kit by Cometic
  • KPMI® C674 Bronze Standard Valve Guides
  • KPMI® S.S. Black Diamond™ Valves, Stock Head Dia.

The product image may not be accurate on the page. Please refer to the description and specifications before purchasing.

Installation Instructions Click Here
Type Intake/ Exhaust
Retainer Material Titanium 
Intake Valve Lift 0.440"
Intake Installed Height 1.215"
Intake Seat Pressure 40#
Intake Open Pressure 147#
Intake @ Lift 0.440"
Exhaust Valve Lift 0.440"
Exhaust Installed Height 1.365"
Exhaust Seat Pressure 70#
Exhaust Open Pressure 203#
Exhaust @ Lift 0.440"
Valve Type  Intake/ Exhaust
Valve Material Black Diamond™ Stainless
Coating Black Nitroneg
Intake Head Diameter 35.00mm/ 1.378"
Intake Stem Diameter 5.5mm/ 0.2158"
Intake Tulip 20º
Intake Overall Length 3.315"
Exhaust Head Diameter 30.00mm/ 1.181"
Exhaust Stem Diameter 5.0mm/ 0.1957"
Exhaust Tulip 20º
Exhaust Overall Length 3.310"
Remarks Standard
Guide Type Intake/ Exhaust
Guide Material C674 Bronze
Reference See Figure 1
Intake Outside Dia.: (G) 0.4360"/ Std.
Intake (A) 0.495"
Intake (B) 0.520"
Intake (C) 0.650"
Intake (D) 0.760"
Intake (E) 0.480"
Intake (F) 0.2155"
Exhaust Outside Dia.: (G) 0.4360"/ Std.
Exhaust (A) 0.580"
Exhaust (B) 0.605"
Exhaust (C) 0.740"
Exhaust (D) 0.890"
Exhaust (E) 0.480"
Exhaust (F) 0.1955"
Unique Identifier No. FR327789_01GAUSt


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