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Cylinder Head Service Kit, 0.440" In and 0.405" Ex Lift, Honda®, CRF™ 450R / RX / WE, 2017-2019

Cylinder Head Service Kit, 0.440" In and 0.405" Ex Lift, Honda®, CRF™ 450R / RX / WE, 2017-2019


Regular price $499.01 USD
Regular price $499.01 USD Sale price $499.01 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 Intake 0.440" Valve Lift, Exhaust 0.405" Valve Lift
  • Top End Gasket Kit by Cometic
  • KPMI® C630 Bronze Standard Valve Guides
  • KPMI® S.S. and Inconel® White 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 1.340"
Intake Seat Pressure 50#
Intake Open Pressure 162#
Intake @ Lift 0.440"
Exhaust Valve Lift 0.405"
Exhaust Installed Height 1.360"
Exhaust Seat Pressure 90#
Exhaust Open Pressure 220#
Exhaust @ Lift 0.405"
Valve Type  Intake/ Exhaust
Valve Material Intake- White Diamond® Stainless
Exhaust- White Diamond® Inconel®
Coating Hard Chrome
Intake Head Diameter 38.00mm/ 1.496"
Intake Stem Diameter 5.0mm/ 0.1960"
Intake Tulip 20º
Intake Overall Length 3.080"
Exhaust Head Diameter 31.00mm/ 1.220"
Exhaust Stem Diameter 5.0mm/ 0.1955"
Exhaust Tulip 23º
Exhaust Overall Length 3.165"
Remarks Standard
Guide Type Intake/ Exhaust
Guide Material C630 Bronze
Reference See Figure 1
Intake Outside Dia.: (G) 0.4360" / Std.
Intake (A) 0.535"
Intake (B) 0.535"
Intake (C) 0.590"
Intake (D) 0.670"
Intake (E) 0.433"
Intake (F) 0.1960"
Exhaust Outside Dia.: (G) 0.4360" / Std.
Exhaust (A) 0.630"
Exhaust (B) 0.630"
Exhaust (C) 0.730"
Exhaust (D) 0.870"
Exhaust (E) 0.433"
Exhaust (F) 0.1955"
Unique Identifier No. FR327789_01GAUSt

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