SRAM 900 Front Hub - 15x110mm Boost - 28 Hole - 6-Bolt Disc - Black

Sealed Cartridge Bearings | Double Time 4-Pawl Engagement | Seeker Angled Flanges | Tool-Free End Cap Conversion | Boost Spacing | MTB Trail & XC Hub | Made in Taiwan

The SRAM 900 front hub delivers mid-range performance with high-end features at an accessible price point. Designed for modern mountain bikes with Boost spacing, this hub features SRAM's proven Double Time four-pawl engagement system for quick pedal response and the innovative Seeker flange design that optimises spoke geometry for improved wheel stiffness and durability. Sealed cartridge bearings provide smooth rolling and weather protection, while the tool-free end cap system allows quick conversion between different axle standards without needing a workshop. At just 160 grams for the 28-hole Boost version, this hub balances light weight with robust construction suitable for cross-country, trail, and all-mountain riding. The 15x110mm Boost spacing is standard on modern MTB forks and provides increased stiffness and improved spoke bracing angles compared to older 15x100mm standards. The black anodised aluminium construction looks sharp and resists corrosion, while the 6-bolt disc interface works with any standard disc rotor. SRAM designed the 900 series to bring premium hub technology down to a more affordable price bracket, making features like sealed bearings, four-pawl engagement, and angled flanges accessible to riders who don't need top-tier XO or XX1 hubs but still want excellent performance and reliability. Whether you're building custom wheels, replacing a damaged hub, or upgrading from a basic OEM hub, the SRAM 900 delivers genuine performance improvements without breaking the bank.

Perfect For These Riders

Key Features

Specifications

Understanding Boost Spacing - 15x110mm

What is Boost spacing and why does it matter?

Boost vs Standard comparison:

Check your fork dropouts before purchasing. If your fork has 110mm spacing between the inner faces of the dropouts, you need a Boost hub. If it's 100mm, you need a standard hub. The SRAM 900 series is available in both configurations (this listing is the Boost version).

SPEEDBALL Sealed Cartridge Bearings

Why SPEEDBALL bearings are special:

Sealed vs Loose Ball bearings:

SRAM's SPEEDBALL bearings represent a significant quality upgrade over budget hubs. You'll feel the difference in smoother coasting and better weather resistance.

Seeker Angled Flange Design

What makes Seeker flanges different:

Real-world benefits:

Seeker is one of SRAM's clever innovations that delivers measurable performance improvements. It's a feature that trickled down from their XO and XX1 hubs to the more affordable 900 series.

Front Hub vs Rear Hub - Key Differences

Why front hubs are simpler (and this is a front hub):

This is a FRONT hub only. If you're building a complete wheelset, you'll also need a SRAM 900 rear hub (sold separately). Make sure the rear hub you choose matches your cassette type (Shimano HG, SRAM XD, or SRAM XDR) and has the same spoke count (28H).

28 Hole Spoke Count - Strength vs Weight

Why 28 holes is the sweet spot for many riders:

Common spoke counts and their applications:

Important: Your rim and rear hub must also be drilled for 28 holes. You cannot mix spoke counts - if the front hub is 28H, the rim must be 28H as well.

J-Bend Spoke Interface

J-bend vs Straight Pull spokes:

Advantages of J-bend:

For this 28H hub, you'll need 28 J-bend spokes in the correct length (calculate using spoke calculator based on your chosen rim's ERD).

Tool-Free End Cap System

Why tool-free end caps matter:

Included Torque Caps:

What are Torque Caps? RockShox Torque Caps are larger-diameter end caps that increase the contact area between the hub and fork dropout. This creates a stiffer connection, reducing axle flex and improving steering precision. They only work with forks that have compatible dropout recesses. If your fork doesn't have Torque Cap compatibility, use the standard 21mm caps included.

6-Bolt Disc Brake Interface

6-bolt vs Centrelock rotor mounting:

Advantages of 6-bolt:

Rotor bolt torque specification: Disc rotor bolts should be torqued to 6.2 Nm (55 in-lb). Use a torque wrench and Loctite 243 (blue) threadlocker to prevent loosening. Always use new bolts if possible - rotor bolts can stretch and lose clamping force when reused multiple times.

Flange Dimensions and Spoke Calculations

Hub flange measurements (for wheel builders):

What these numbers mean:

Spoke length calculation resources:

160 Grams - Lightweight MTB Hub

How 160g compares to other hubs:

Why weight matters on wheels:

At 160 grams, the SRAM 900 hits the sweet spot between light weight and durability. You could go lighter with a carbon or titanium boutique hub, but you'd sacrifice reliability and pay significantly more for minimal weight savings.

Building Wheels with the SRAM 900 Hub

What else you'll need for a complete wheel:

Spoke recommendations for MTB use:

Recommended spoke pattern:

Professional wheel building recommended: If you've never built a wheel before, have a professional wheel builder lace and tension your wheel. Properly tensioned spokes are critical