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Tuesday 26 July 2022

Kibblewhite Precision Machining

Indian Scout Valvetrain System

Pacifica, California based Kibblewhite Precision Machining Inc., has an over 80 year pedigree as one of the market's leading and innovative performance valve train engineers. Still family owned and operated, KPMI is most closely associated with Harley-Davidson valve trains, but the company actually makes products for a wide range of powersports (and automotive) industry vehicles - as both OEM replacement and performance upgrade components.
Since the end of last year KPMI has been designing and manufacturing valvetrain for Indian Motorcycle applications. The range of applications will soon include all (2020-2022) Indian Challengers, but seen here is a round-up of the company's valve train components for 8-valve Indian Scout 1200s from 2015-2019.
Beehive Spring Kit


Manufactured in heat treated steel with 0.435" lift, this Beehive spring kit is compatible with the OEM tappet lash adjustment system and KPMI shim conversion tappets. Designed to work well with the OEM integrated Seal/Base or, as included with this kit, KPMI's own #71048-8 OEM replacement seals for "a more complete performance valvetrain solution."

Racing Spring Kit

Manufactured in titanium and heat treated steel with 0.450" lift, these racing springs are compatible with the OEM tappet lash adjustment system and the KPMI's own shim conversion tappets. The seals included in these kits are intended for use with OEM guides or with KPMI guides if installed with KPMI 71016-8 seals. Offered with titanium and heat treated steel retainers.

Manganese Bronze 'Engine Builder' Valve Guides 


Designed with the "price conscious builder in mind, you can expect the same exacting KPMI tolerances from these standard manganese bronze guides, but with reduced toughness and durability compared to premium C630 nickel aluminum bronze valve guides.
"The softer manganese guides are easily reamed, and then can be delicately finished with our high quality ball hones. Now, with any battery operated or electric drill, you can ream and hone manganese valve guides in less time and without access to the kind of expensive honing equipment required to properly size tough nickel bronze guides."

Black Diamond Stainless Valves

Available in standard or +1 mm over size, all KPMI Black Diamond stainless steel valves are impregnated by a special German process to a depth of .002, with a surface build-up of .0002. This proprietary Black Diamond process "improves wear properties, reduces friction, and provides resistance to corrosion and wear that is superior to chrome and nickel electrolysis plating.
"Each valve is designed using Finite Element Analysis (FEA) software, and profiles are tested on our computerized flow bench. Black Diamond Valves are lightweight, strong, one piece forgings with profiles that provide excellent flow characteristics."

Shim-on-Bottom Tappets


Manufactured from billet aircraft alloy steel, these 31.15 mm OD tappets are designed using advanced FEA software. "This software allows our engineers to lighten the tappets without sacrificing strength, which creates the strongest and lightest tappets possible. The tappets are then machined from billet aircraft quality steel. After machining the tappets undergo a proprietary heat treatment process that creates a hard surface and a nonbrittle core."
These materials and processes maximize toughness and wear resistance. To finish, the tappets are OD ground and then the contact area is lapped and polished to create a very flat and smooth surface for the cam to run against. KPMI tappets are run in high performance automotive and motorcycle racing applications including Motocross, Flat Track Racing, Road Racing, Drag Racing, and Land Speed Racing.

DLC Coated Tappets

These 31.15 mm billet aircraft alloy steel DLC (Diamond Like Coated) shim-on bottom tappets undergo a low temperature Physical Vapour Deposition (PVD) process to coat them with an extremely hard and long service life, very low coefficient of friction DLC film to help the tappet to maintain durability in extreme duty situations. Although KPMI recommends never running a camshaft off the edge of the tappet, this coating may help increase durability in these applications.

OEM Replacement 5.5 mm Stem x 0.435" Red Viton Guide Seals


KPMI solid Viton valve guide stem seals are resistant to high temperatures, petroleum products and the corrosive gasses that are the by-products of combustion. "These lift valve stem seals deliver optimum fitment and allow for maximum lift and service life. They retain their ability to seal in situations where other materials could harden and allow oil to enter the combustion chamber causing detonation, carbon build up and a loss of power." They are sold in packs of eight.

Red Viton, 5.5 mm Stem x 0.360" Guide Seals

These KPMI Red 100% Viton valve stem seal designs with 5.5 mm stem x 0.360" have all the design and materials advantages, resistance and durability characteristics of the OEM replacements, but the shorter duration make them "truly the racers choice."