INOUE BORING
SUZUKI GT380 φ 54.0 mm STD ICBM Aluminum Sleeve Finish Cylinder Processing
SUZUKI GT380 φ 54.0 mm STD ICBM Aluminum Sleeve Finish Cylinder Processing
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About This Service
This is a cylinder rebuild service for SUZUKI GT380 (Φ 54 mm).
Upon receipt of your cylinder, we will rebuild it and return it to you.
Please send us only the cylinder and the corresponding piston, with payment in advance.
We will install an aluminum sleeve plated with nickel-silicon-carbide (hardness second only to diamond) and ensure proper piston clearance before returning it to you.
This rebuild also features Inoue Boring’s original “Bridge-Port” specification, a unique pillar-type port structure designed to enhance durability and gas flow stability — ideal for high-performance and long-lasting results.
Never Wears Out. Seizure-Proof. Lightweight.
- Ride right away—no break-in required
- Exceptionally long-lasting
- One-third the weight of cast iron
- 5 x the heat transfer of cast iron
- Rust-free
What is ICBM™ Processing?
- Remove the original cast-iron sleeve.
- Install a precision nickel-silicon-carbide-plated aluminum sleeve.
- Ride with a lightweight, ultra-durable cylinder that preserves itself as you go.
We Buy Your Spare Cylinders
Upgraded to ICBM cylinders? Sell your leftover originals to us—just submit a buy-back request through our inquiry form.
Need pistons supplied? Request a quote on our Estimate Request page. Processing takes about 20 business days.
All work is completed in our insured, domestic facility, and every component is quality-guaranteed. Ride with confidence—preserve your engine for the next generation.
Frequently Asked Questions
▶ What is ICBM™ cylinder processing?
ICBM™ processing replaces the original cast-iron sleeve with a precision nickel-silicon-carbide-plated aluminum sleeve. The result is a cylinder that is lightweight, seizure-proof, rust-free, and exceptionally long-lasting — with no break-in period required.
▶ What is the Bridge-Port specification?
Inoue Boring’s original Bridge-Port specification uses a pillar-type port structure designed to enhance durability and gas flow stability, ideal for high-performance and long-lasting results.
▶ What do I need to send for the rebuild service?
Please send us only the cylinder and the corresponding piston, with payment in advance. Upon receipt, we will rebuild it and return it to you.
▶ How long does processing take?
Processing takes approximately 20 business days.
▶ Can you supply pistons?
Yes. If you need pistons supplied, please request a quote on our Estimate Request page.
▶ Do you buy back original cylinders?
Yes. If you have upgraded to ICBM cylinders and have leftover originals, you can sell them back to us via our inquiry form.
Learn More About ICBM™ Technology
- What Is ICBM™ Technology? A New Future for Vintage Engines
- H2 Cylinders ICBM® — Detailed Specifications
- Why We Built a Billet H2 Cylinder
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ICBM™ gives your engine alive again!
- Long-lasting super durability
- Preserve your engine while riding
- 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.
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
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