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90mm Piston Rings for 420cc Big Block Honda Clone
90mm piston rings installed on a Predator 420 Big Block Honda Clone piston
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90mm Piston Rings for 420cc Big Block Honda Clone

Part Number: 190F-12300-A
Online Price: $16.99
90mm Standard Piston Ring Set for Predator 420 & Honda GX390/GX420 Big Block Clone Engines
Availability: In Stock.

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Description

90mm Piston Ring Set for Predator 420 and Big Block Clone Engines


Restore compression, reduce oil consumption, and keep your Big Block Honda Clone engine performing at its best with this 90mm Standard Bore Piston Ring Set. Designed as a direct replacement for the factory 90mm piston used in many 420cc Honda-style engines, these piston rings are ideal for engine rebuilds, maintenance, and performance refreshes on mini bikes, go-karts, utility vehicles, and industrial engines.


Compatible with the popular Predator 420, bored-out Honda GX390, and many other Honda-clone Big Block engines, this ring set helps restore proper cylinder sealing for improved power, throttle response, and engine efficiency.


Features & Benefits

OEM Standard 90mm Replacement

Designed to fit standard 90mm pistons found in many Honda-style Big Block engines, making it an excellent choice for stock rebuilds and mild performance engines.

Restore Engine Compression

Replacing worn piston rings helps:

  • Restore cylinder compression
  • Improve horsepower and torque
  • Reduce oil consumption
  • Minimize blow-by
  • Improve cold starting
  • Increase overall engine efficiency

Precision Manufactured

Manufactured from high-quality materials for dependable sealing, excellent wear resistance, and long service life in both recreational and performance applications.

Ideal for Engine Rebuilds

Perfect for:

  • Predator 420 rebuilds
  • Mini bike engines
  • Racing go-karts
  • Off-road buggies
  • Custom Big Block Honda Clone builds


Ring Specifications

Specification

Dimension

Bore Size

90mm (Standard Bore)

Top Ring Thickness

.078" (2.0mm)

Second Ring Thickness

.078" (2.0mm)

Oil Ring Assembly Thickness

.104" (2.65mm)

Engine Compatibility

Fits many Honda-style Big Block engines equipped with a 90mm standard bore piston, including:

  • Predator 420
  • Most 420cc Honda Clone Engines

Important: Specifications can vary between manufacturers. Always measure your existing piston rings and ring grooves before ordering to ensure proper fitment.


Installation Notes

  • Designed for standard 90mm pistons
  • Verify ring end gap during installation
  • Check ring groove width before assembly
  • Professional installation or experienced engine building practices are recommended
  • Hone or inspect the cylinder before installing new rings for optimal sealing and performance


Perfect For

  • Predator 420 engine rebuilds
  • Big Block Honda Clone engines
  • Performance mini bikes
  • Racing go-karts
  • Utility vehicles
  • Industrial engines
  • Off-road applications

FAQ

What engines do these 90mm piston rings fit?

These rings fit many Honda-style Big Block engines equipped with a standard 90mm piston, including Predator 420,  and certain Big Block Honda Clones


Are these standard-size piston rings?

Yes. These are standard-size (90mm) replacement rings designed for standard bore cylinders and pistons.


Can I use these on an oversized piston?

No. These rings are intended for standard 90mm pistons. Oversized pistons require matching oversized ring sets.


How do I verify compatibility?

Measure your existing piston, ring grooves, and old ring thicknesses before ordering. Dimensions can vary slightly between manufacturers.


Should I hone the cylinder before installing new rings?

Yes. A properly honed cylinder helps new piston rings seat correctly, improving compression, oil control, and engine longevity.


What are the symptoms of worn piston rings?

Common signs include reduced compression, excessive oil consumption, blue exhaust smoke, poor throttle response, blow-by, and reduced engine performance.


Are these rings suitable for racing engines?

Yes. These rings are suitable for both stock rebuilds and many performance Big Block Honda Clone engines used on mini bikes, go-karts, and other high-performance applications, provided the piston and cylinder dimensions match the listed specifications.

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