Wiseco Top End Bearing 18x22x19.8mm for KTM 250 SX 1992-2024 B1037

Top-end bearings are critical wear items in high-RPM two-stroke engines, and OEM replacements often lack the durability needed for sustained racing or aggressive trail riding. The Wiseco B1037 delivers superior longevity through precision engineering and premium materials, ensuring your KTM 250 SX maintains reliable power delivery across thousands of riding hours. This is a direct OEM replacement that restores—or exceeds—factory performance standards.

Wiseco's high-silicon aluminum alloy construction provides the strength required for extreme engine speeds while remaining lightweight. The case-hardened design resists wear from constant piston and connecting rod motion, reducing the risk of catastrophic engine failure. Whether you're rebuilding after a top-end refresh or performing preventive maintenance, this bearing is a non-negotiable component for reliability.

• Bore: 18mm
• OD: 22mm
• Width: 19.8mm
• High-silicon aluminum alloy
• Case-hardened construction
• Precision-manufactured tolerance
• High-RPM rated
• Lightweight design
• OEM fitment: KTM 250 SX (1992–2024)
• Bolt-in installation