Item No :
ACB518H8 45/45Size (d*D*B) :
40x51.8x8 mmMaterial :
Gcr15.chrome steelBrand :
Famous brand/RMO/Neutral/OEM&ODMLead Time :
normally 3-5 daysWeight :
0.033KGMOQ :
50 pcsShipping Port :
Guangzhou, Ningbo, ShanghaiACB518H8 45/45 Bike Headset Bearing
⚙️Product description:
The ACB518H8 45/45 Angular Contact Bearing is specially designed for bicycle headset systems with a 45°×45° contact angle. It provides smooth steering control and excellent axial and radial load capacity. With sealed structure and high‑precision steel, it offers long service life, water resistance, and reliable performance under MTB and road cycling conditions. Ideal for OEM and aftermarket replacement.

| Model No. | ACB518H8 45/45 Bike Headset Bearing |
| Size | 40x51.8x8mm |
| Contact Angle | 45°×45° |
| Material | Chrome steel Gcr15 |
| Package | Plastic Tube/single box + Carton + Pallet |
| Service | OEM/ODM |
| Small order | Accept |
| Shipping Port | Guangzhou, Ningbo, Shanghai |
| Payment | 100% T/T, or 30% T/T In Advance ,70% T/T After Finished Production |
• 45° × 45° angular contact
• Smooth steering performance
• High precision and durability
• Sealed and corrosion‑resistant
• Compatible with multiple headset systems
• OEM replacement available
| Bearings No. | d*D*H(mm) | Weight (G) |
| ACB305418H6.3-45/45 | 30.5*41.8*6.3 | 30 |
| ACB307418H7.7-45/45 | 30.7*41.8*7.7 | 30.1 |
| ACB3144H6.3-45/45 | 31.4*44*6.3 | 30.2 |
| ACB31448H6.3-45/45 | 31.4*44.8*6.3 | 32.6 |
| ACB32438H7-45/45 | 32.4*43.8*7 | 23 |
| ACB32418H6-45/45 | 32.8*41.8*6 | 16 |
| ACB3344H6-36/45 | 33*44*6 | 21 |
| ACB33438H7-30/45 | 33.05*43.8*7 | 23.8 |
| ACB3345H7-45/45 | 33.5*45*7 | 26.2 |
| ACB3446H7-45/45 | 34.1*46*7 | 25 |
| ACB34468H7-45/45 | 34.1*46.8*7 | 27.7 |
| ACB34469H7-45/45 | 34.1*46.9*7 | 28 |
| ACB3544H5-90/90 | 35*44*5 | 16 |
| ACB3544H5.5-36/45 | 35*44*5.5 | 32 |
| ACB354535H7.3-45/45 | 35*45.35*7.3 | 22.3 |
| ACB3547H8-45/45 | 35*47*8 | 29.9 |
| ACB36458H6.5-45/45 | 36.8*45.8*6.5 | 18.9 |
| ACB3748H7-45/45 | 37*48*7 | 27 |
| ACB37489H6.5-36/45 | 37*48.9*6.5 | 25.9 |
| ACB3749H6.5-36/45 | 37*49*6.5 | 25.25 |
| ACB3749H7-36/45 | 37*49*7 | 28.1 |
| ACB3749H7-45/45 | 37*49*7 | 28.8 |
| ACB4051H6.5-36/36 | 40*51*6.5 | 24.8 |
| ACB4051H8-36/45 | 40*51*8 | 29.3 |
| ACB4051H7-45/45 | 40*51*7 | 31 |
| ACB40515H7-45/45 | 40*51.5*7 | 30.8 |
| ACB40518H7-45/45 | 40*51.8*7 | 30.8 |
| ACB40518H8-36/45 | 40*51.8*8 | 32.6 |
| ACB40518H7.5-36/45 | 40*51.8*7.5 | 33 |
| ACB40518H8-45/45 | 40*51.8*8 | 33.1 |
| ACB40518H8-90/90 | 40*51.8*8 | 33.1 |
| ACB40519H7-45/45 | 40*51.9*7 | 29.6 |
| ACB40519H8-45/45 | 40*51.9*8 | 32.6 |
| ACB4052H6.5-36/45 | 40*52*6.5 | 29.2 |
| ACB4052H7-90/90 | 40*52*7 | 30.9 |
• MTB Mountain bikes
• Road bikes
• BMX / DH bikes
• Fixed gear Track bike
• Integrated headset replacement
• Bicycle maintenance aftermarket
| 1. Keep clean | 2. Use with caution | 3. appropriate tool | 4. Hot-loading | 5. Be careful of rust |
| Dust will have a bad effect on the bearing, so keep the surrounding clean. | Strong impact during use can easily cause scratches and indentations. | Avoid replacing existing tools, and use appropriate tools. | Bearings are precision parts, so hot installation is recommended. | Sweat on your hands during operation will cause rust, so it is best to wear gloves. |
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