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M-Part Headset Bearing 40.0 x 51.9 x 8 – 45°/45° | High-Performance Cartridge Bearing for Headsets
M-Part Headset Bearing 40.0 x 51.9 x 8 – 45°/45° | High-Performance Cartridge Bearing for Headsets
M Part

M-Part Headset Bearing 40.0 x 51.9 x 8 45 Degree/45 Degree - Silver

£21.99
Pre-Order

With Pre-Order, you can purchase the latest items added to our store in advance of them arriving with us.

Your Pre-Order is prioritised (at no additional charge); meaning that as soon as the product arrives with us, we can wrap it straight back up; ready for collection via Click & Collect or despatch to you — it often never even hits the stock room shelves!

Pre-Launch

With Pre-Launch, the date when we expect to receive the product ourselves is still a little too hazy to be confident in accepting Pre-Orders.

So, instead, you can submit your email address against the item you are interested in and we will email you as soon as stock arrives on the system.

Estimated Delivery & Collection Dates

Estimated Delivery & Collection Dates are given on Pre-Order and Pre-Launch products. They are for indication purposes only and can change at any time without notice.

The dates we provide are based on indications given by our suppliers. Whenever we get updated information from our suppliers we will endeavour to update the Estimated Delivery & Collection Dates provided on product pages.

We estimate this will be ready for despatch to you or collection via Click & Collect on Undetermined

M-Part Headset Bearing 40.0 x 51.9 x 8 45 Degree/45 Degree - Silver

Brand:M Part

Code:CB-780

M-Part Headset Bearing 40.0 x 51.9 x 8 – 45°/45° | High-Performance Cartridge Bearing for Headsets

Upgrade or replace your headset bearings with the high-precision M-Part Headset Bearing, designed specifically for bicycles and engineered to match the quality and specifications used by leading bike manufacturers worldwide.

This cartridge bearing is built to fit a wide range of integrated and semi-integrated headsets, offering smooth steering performance, maximum durability, and weather-sealed protection. Manufactured with premium materials including CrMo (chromoly) ball bearings and races, this headset bearing delivers performance that meets or exceeds OEM standards.

  • Precision Fit – Dimensions: 40.0 x 51.9 x 8mm, 45°/45° contact angles
  • Premium Materials – CrMo races and ball bearings (HRC 61-66 hardness)
  • High Tolerance – Built to ABEC-3 precision standards
  • Smooth Operation – Nylon retainer ensures quiet, frictionless rotation
  • Long-Lasting Protection – Features LLU full-contact rubber seals to block out dirt and moisture
  • Factory-Grade Lubrication – Filled with Multemp SRL (Kyodo Yushi) high-performance grease

Ideal For:

  • Road bikes, mountain bikes, gravel bikes, e-bikes
  • Integrated & semi-integrated headset systems
  • High-performance replacement or upgrade

Maintain smooth steering, reduce wear, and ride with confidence, choose the M-Part 40.0 x 51.9 x 8 headset bearing for unmatched reliability and precision.

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