• Kawasaki H1 500SS LABYRI crank center labyrinth seal — iNOUE BORING Japan
  • LABYRI non-contact metal labyrinth crank center seal for Kawasaki H1 500SS — iNOUE BORING
  • Kawasaki H1 500SS crank center seal LABYRI — anodized aluminum, precision-machined in Japan
  • LABYRI labyrinth seal detail — zero wear, zero friction, zero energy loss — iNOUE BORING Japan
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iNOUE BORING

Kawasaki H1 500SS Crank Center Labyrinth Seal LABYRI

Kawasaki H1 500SS Crank Center Labyrinth Seal LABYRI

$409.00
$409.00
Sale Sold out
Shipping calculated at checkout.

Item Specifics

Condition New Machine Type N/A
Items Included N/A Manufacturer Part # LABYRI
Compatible Model H1 500SS Material Aluminum (Anodized)
Superseded Part N/A Vintage Part No
Engine Type 2-Stroke Brand Kawasaki
Type Crank Center Labyrinth Seal Interchange Part # N/A
Manufacturer Warranty N/A OE/OEM Part # N/A
Country/Region of Manufacture Japan Finish Anodized
Performance Part Yes UPC N/A


This is a crank center labyrinth seal specifically designed for the Kawasaki H1 500SS.
Manufactured and precision-machined by Inoue Boring, this seal offers outstanding durability and airtightness, ideal for high-performance 2-stroke engines.

  • Compatible Model: Kawasaki H1 500SS
  • Type: Center Labyrinth Seal (LABYRI)
  • Manufacturer: Inoue Boring (Japan)
  • High-precision machining for optimal sealing performance
  • Made in Japan – trusted by vintage motorcycle restorers and tuners

Ensure proper crankcase pressure management and long engine life with this high-quality replacement part.

The Biggest Weakness of 2-Stroke Engines — Solved

The biggest weakness of 2-stroke engines — center seal failure — is finally solved with the LABYRI labyrinth seal.

With LABYRI, you no longer need to fear seal blowout.
This advanced design eliminates pressure loss and energy leakage, delivering:

  • Sharper throttle response
  • Smooth, resistance-free rotation
  • Zero energy loss

Experience a dramatic improvement in pickup and engine behavior, all thanks to a precision-engineered solution trusted by professionals.

LABYRI — Fully Original Proprietary Design

This is our fully original, proprietary product —
a non-contact, metal labyrinth-style crank center seal:
LABYRI by INOUE BORING.

Unlike conventional contact-type seals, LABYRI is non-wearing.
Thanks to its precision-engineered labyrinth structure, it eliminates friction and ensures:

  • Zero wear over time — truly built to last
  • Zero energy loss — no friction, no drag
  • Smooth, resistance-free crank operation

Because it’s a non-contact metal seal, LABYRI not only improves engine responsiveness, but also delivers eternal sealing performance — a revolutionary solution for 2-stroke engines.

Proudly developed and manufactured in Japan by INOUE BORING.

Key Features & Advantages

  • No modification required — fits directly onto the stock crankshaft without machining
  • Crisp, defined appearance — adds a sharp, functional aesthetic to your engine
  • Anodized finish for corrosion resistance — built to withstand harsh conditions
  • OEM-like design — faithfully follows original shape for seamless integration
  • Precision inner bore — anodizing is intentionally omitted on the inner diameter to preserve dimensional accuracy
  • Zero friction — non-contact design means no rotational drag
  • Fully metal construction — unlike rubber seals, this will never degrade with age

Manufactured by INOUE BORING — Trusted by performance engine builders across Japan.


Compatibility

Year Make Model Submodel Notes
all model years Kawasaki H1 500SS


Frequently Asked Questions

▶ What is a labyrinth seal and how does it differ from a conventional seal?

A labyrinth seal is a non-contact, metal-to-metal sealing mechanism that uses a precision-engineered maze-like structure to prevent gas leakage without physical contact. Unlike conventional rubber contact seals, LABYRI never wears out, generates zero friction, and delivers permanent sealing performance.

▶ Does LABYRI require any modification to the crankshaft?

No modification is required. LABYRI fits directly onto the stock Kawasaki H1 500SS crankshaft without any machining or alteration.

▶ What performance improvements can I expect?

By eliminating crankcase pressure loss and energy leakage, LABYRI delivers sharper throttle response, smoother resistance-free rotation, and zero energy loss — resulting in a dramatic improvement in pickup and overall engine behavior.

▶ Why is the inner bore not anodized?

Anodizing is intentionally omitted on the inner diameter to preserve dimensional accuracy and ensure a precise fit on the crankshaft. The outer surfaces are fully anodized for corrosion resistance.

▶ Can I order for a different model or custom specification?

Please fill out the form below.


Learn More About iNOUE BORING Technology


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ICBM™ gives your engine alive again!

  1. Long-lasting super durability
  2. Preserve your engine while riding
  3. Feel the engine's pulse forever!

“We want to create a cylinder that doesn't wear down...” This has been Inoue Boring’s long-held dream. This technology dramatically improves the durability of the cylinder bore by manufacturing an aluminum sleeve and applying a special plating to the inside diameter.

LEARN MORE

Why ICBM™ is "Revolutionary”

✔ Exceptional wear resistance
✔ Lightweight
✔ Low friction (reduces ring wear)
✔ Highly resistant to seizure
✔ Excellent heat dissipation
✔ Uniform expansion rate
✔ And it’s rust-resistant!

TESTIMONIALS

”Elegance Reborn: My Mach III Runs Like New”

My Kawasaki Mach III is over 50 years old. Many parts were worn out, so I used Inoue Boring’s modern engine work to bring it back. With  ICBM™ treatments, it runs smooth and strong. It won First Place at a restoration contest hosted by Inoue Boring. This bike is old—but alive.

-Mr.Hirakawa　Kawasaki H1 Owner　
Japan

”Back to Life: My Orange H1-B with ICBM™”

“After years in storage, I brought my H1-B back with Inoue Boring’s ICBM™ treatment. The old cast-iron sleeve was replaced with an aluminum one, letting me return to the standard bore. I even added a bridge port. It’s not about more power—it’s about bringing back the ride I remember.”

-Mr. Katsumi Taguchi　Kawasaki H1-B Owner
Japan

READ MORE

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