iNOUE BORING
YAMAHA RZ250R Crankshaft Rebuilt Centered W/ small-end b/g Inoue Boring Japan
YAMAHA RZ250R Crankshaft Rebuilt Centered W/ small-end b/g Inoue Boring Japan
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RZ250R crankshaft (with small end B/g). Bearings, connecting rods, washers, and plates are all new!
Item specifics
| Condition | New | Machine Type | N/A |
| Items Included | N/A | Manufacturer Part | N/A |
| Compatible Model | RZ250R | Material | steel |
| Superseded Part | N/A | Vintage Part | No |
| Engine Typev | 2-Stroke | Brand | YAMAHA |
| Type | Crankshaft | Interchange Part | N/A |
| Manufacturer Warranty | 3 Months | OE/OEM Part | no, N/A |
| Country/Region of Manufacture | Japan | Finish | Polished |
| Performance Part | Yes | UPC | N/A |
・This Yamaha RZ250R crankshaft has been rebuilt and centered with small-end bearings, ensuring optimal performance for your motorcycle engine.
・ Made of high-quality cast iron material, this crankcase is a perfect fit for your Yamaha engine.
・The polished finish adds to the aesthetic appeal of your bike.
・This item is perfect for those looking to upgrade their motorcycle engine crankcase.
・With its precise construction and excellent quality, it is sure to improve the overall performance of your Yamaha RZ250R.
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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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