Products in Excellent condition look brand new — with no physical flaws, scratches or scuffs — and include all original parts and accessories. The product will be in its original packaging or a suitable replacement box.
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Products in Satisfactory condition show minor to moderate signs of use that affect cosmetic appearance but have no impact on performance. A satisfactory product does not include dents, chips, cracks, or deep scratches. It may not contain the original packaging or some parts and accessories.
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Products in Fair condition operate as intended, but show more significant scratches, dents, or chips. For example, an exhaust returned to Dennis Kirk with a dent or large scratch that doesn’t affect the product's performance. It may not contain the original packaging or some parts and accessories.
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Product Information
JIMS Manual Compression Release Valves
Ease your starts with Jims Manual Compression Release Valves, a pro-grade add-on for high-compression Harley engines. These valves vent cylinder pressure with a tap, making it easier to crank your big-bore motor without killing your starter. Easy to install, they thread into specific Harley heads, offering a quick upgrade for riders building hot engines. Built from tough steel, they handle heat and pressure, ensuring reliable releases ride after ride. Perfect for custom builders or performance junkies, they’re a must for taming high-compression beasts. The manual design gives you control, letting you pop the valves when needed for smooth starts. Trust Jims to make your Harley’s big heart easier to fire with these precision valves.
Install these in your high-compression, big-inch motor and give your starter some help
Install by simply drilling and tapping each cylinder head and thread in the self-sealing release valves
Can be installed in all Big Twin, XL and Buell motors
Made in the U.S.A.
Included Items:
(2) Compression release valve
Instructions
Mfg #: 727K
Part #: H28045
Type: Compression Release Valve
Units: Pair
Weight: 0.10 lbs
Vendor Part Number(s):DS196400
Fitment for JIMS Manual Compression Release Valves