SRAM DUB Installation Mistakes That Can Ruin Your Set-Up

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The SRAM DUB [paid link] (Durable Unified Bottom Bracket) system is designed for simplicity and durability across a broad range of bottom bracket standards. Yet despite its user-friendly engineering, improper installation remains a leading cause of creaking, premature wear, and performance issues. Whether you’re installing it for the first time or servicing an existing set-up, avoiding key mistakes is essential to maintaining drivetrain integrity and long-term reliability.

This guide explains the most common SRAM DUB [paid link] installation mistakes, why they matter, and how to avoid them.

Understanding the SRAM DUB System

The SRAM DUB [paid link] system uses a single spindle diameter—28.99 mm—to unify compatibility across a wide range of bottom bracket shell standards, such as BSA, BB30, PF30 [paid link], and BB92. The aim is to simplify crankset selection while improving bearing longevity and system stiffness.

Because DUB interfaces with multiple shell types, precise installation practices are critical. Small errors in fit or torque can have exaggerated effects on bearing load, crank alignment, and frame compatibility.

Incorrect Bottom Bracket Shell Preparation

One of the most common mistakes occurs before the DUB bottom bracket even enters the frame. Improper shell prep compromises fit and long-term performance.

  • Uncleaned Shell Surfaces: Dirt, old grease, or remnants of thread locker can prevent full seating of the bottom bracket cups. This leads to poor alignment and creaking.
  • Shell Facing and Chamfering Ignored: If the frame’s shell faces are not machined properly (especially on threaded shells), the bottom bracket may not install flush. This can create uneven pre-load on the bearings.
  • Shell Measurement Overlooked: Not all bottom bracket shells are created equal. For example, a PF30 [paid link] shell must meet exact dimensional tolerances. Installing a DUB PF30 [paid link] bottom bracket into a shell that’s out of spec will inevitably lead to noise and premature wear.

Using the Wrong Bottom Bracket Variant

SRAM DUB bottom brackets are specific to shell types. Mistaking one variant for another causes irreversible fitment issues.

  • Incorrect Fitment with Press-Fit Models: Trying to use a DUB PressFit 89.5/92 in a BB30 frame, or vice versa, will damage both the bottom bracket and the frame shell.
  • Mixing Standards: Riders sometimes attempt to use a DUB bottom bracket in a shell designed for GXP [paid link] or other non-DUB spindle standards. While spindle adapters exist, they are not a substitute for a correctly matched DUB-specific bottom bracket.

Correct identification of your frame’s shell type and width is vital before selecting and installing a DUB bottom bracket.

Over-Torquing or Under-Torquing the Bottom Bracket Cups

Torque errors are more common than they should be and almost always lead to mechanical issues.

  • Over-Torquing: Excessive torque can crush bearings or distort the shell interface. In threaded shells like BSA, this may also damage the threads.
  • Under-Torquing: Leads to a loose interface, which causes the cups to back out or creak under pedaling load. The manufacturer’s specifications are not suggestions—use a torque wrench [paid link] to tighten exactly to SRAM’s recommended values (typically 35-40 Nm for threaded cups).

Neglecting to Use the Correct Spacers

Spacer misconfiguration is one of the leading causes of poor chainline, crank arm misalignment, and excessive bearing pre-load.

  • Missing Spacers: Certain shell widths require a specific number of spacers to center the crankset properly. Skipping them can shift the chainline and introduce side-loading.
  • Wrong Spacer Placement: Placing spacers on the incorrect side (non-drive vs. drive side) results in uneven crank arm spacing and bearing wear.
  • Misreading the Instructions: DUB uses a very specific spacer scheme based on bottom bracket type and shell width. SRAM provides detailed charts—consult them for your specific setup.

Improper Preload Adjustment on the Crankset

The SRAM DUB crank preload adjuster (on the non-drive arm) must be set correctly to eliminate side play without compressing the bearings.

  • Too Tight: Overloading the preload ring creates excess friction on the bearings and reduces their lifespan significantly.
  • Too Loose: You’ll experience lateral play in the crank arms, especially under torque. This also increases wear on the spindle and bottom bracket shell.
  • Failure to Re-Tension After First Rides: Preload often settles after the first few rides. Failing to recheck and adjust can allow persistent crank arm movement and creaking.

Skipping Thread Locker or Grease Where Required

Friction management is essential in DUB installs. Omitting lubrication or thread locker where required is a major mistake.

  • Threaded BBs: Use a manufacturer-recommended thread locker (such as Loctite 242) to prevent loosening. This is not optional—without it, cups can work loose under riding forces.
  • Press-Fit BBs: Use a press-fit-specific retaining compound or waterproof grease depending on frame manufacturer recommendations.
  • Spindle Interface: Apply a thin layer of grease to the spindle before inserting it into the bottom bracket. This ensures smooth assembly and prevents corrosion-related seizing.

Improper Tool Use

Specialized tools are required for DUB bottom bracket installation. Using the wrong tool can strip cups, crack frames, or improperly seat bearings.

  • Cup Tool Compatibility: Make sure you use the correct DUB-specific bottom bracket cup tool that matches your shell type—SRAM’s BBT-79 tool or equivalent.
  • Press Tools for PF BBs: A quality bearing press [paid link] with perfectly aligned guides is essential. Hammering or forcing the cups with makeshift tools will damage the frame and cups.

Failure to Verify Crank Arm Bolt Torque

After the bottom bracket is installed, proper crank arm torque is critical to final performance.

  • Loose Crank Arm: Under-torqued crank bolts will cause wobbling, clicking sounds, and long-term spindle damage.
  • Over-Tightened Crank Bolt: Leads to crank arm distortion and potential failure at the spindle interface.

Always finish the installation by torquing the crank bolt to SRAM’s recommended value, typically 54 Nm, using a calibrated torque wrench [paid link].

Conclusion

Installing a SRAM DUB bottom bracket is straightforward—but only when every step is executed with precision. From shell preparation to torque settings and spacer placement, every detail matters. Avoiding the installation mistakes outlined above is not just about performance—it’s about preventing premature wear, ensuring safety, and preserving frame integrity.

If you’re unsure about any part of the process, consult a certified mechanic or SRAM’s technical manuals before proceeding. A well-installed DUB system will run quietly, efficiently, and for thousands of miles.