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Prestacycle

Prestacycle UniBlock PRO - 12-Speed Cassette for SRAM XDR Freehub

93151XDR

UniBlock PRO Cassette - Choose Range:
Regular price
$289.00
Regular price
$329.00
Sale price
$289.00
Shipping calculated at checkout.

30-Day Easy Returns

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Premium one-piece CNC Chromoly steel cassette precision-machined from a solid block delivering precise shifting, lighter weight, longer life and greater freehub protection.

Why Riders Upgrade to UniBlock PRO

  • 10 tooth cog exchanged for gears you need more often
  • More Gear ratio options available
  • Easier cleaning & installation
  • Simpler, more flexible Cassette mounting options

Features

PERFORMANCE

  • Maximum Performance 12 Speed Shifting
  • Interchangeable performance on all Drivetrains
  • Ultra-Strong ChroMoly 3D Structure
  • Ultra-Light – less material needed
  • Larger, better-distributed Freehub engagement
  • Easier to Clean
  • Steel XDR locknut included

COMPATIBILITY

  • GEARS: 12 Speed
  • SHIFTING: SRAM
  • FREEHUB: XDR

Bundle Includes:

  • Uniblock PRO SHIMANO 12 speed Cassette (select gear range)
  • XDR Adapter Lockring

Featuring ARC™ Shifting Technology and a 3D single-piece structure, they deliver fast, smooth 12-speed shifting across all major drivetrains while protecting your freehub from wear. Designed for riders who demand durability, compatibility, and pro-level shifting in every gear.

Specifications

11-25T:

Ratios: 11-12-13-14-15-16-17-18-19-21-23-25
Weight: 151 g

11-28T:

Ratios: 11-12-13-14-15-16-18-20-22-24-26-28
Weight: 185 g

11-30T:

Ratios: 11-12-13-14-15-16-17-19-21-24-27-30
Weight: 182 g

11-32T:

Ratios: 11-12-13-14-15-16-17-19-22-25-28-32
Weight: 185 g

11-34T:

Ratios: 11-12-13-14-15-17-19-21-24-27-30-34
Weight: 204 g

11-36T:

Ratios: 11-12-13-14-15-17-19-21-24-28-32-36
Weight: 218 g

11-40T:

Ratios: 11-12-13-15-17-19-21-24-28-32-36-40
Weight: 320 g

Product Information

Greater Freehub Engagement, Smoother Operation

Single block design insures the freehub has MORE engagement no matter what gear your are in. Single cogs from other Cassettes can cut-like-a-knife into freehubs. By increasing and distributing engagement across the entire freehub in any gear, we are reducing torsional loads thus reducing freehub wear and insuring lowest rolling resistance within the freehub. This also makes our Cassettes the safest to use with high-end alloy freehubs. Without any spacers in UniBlock, there is nothing to loose, and nothing you can install incorrectly. Faster cleaning on and off the bike, with quicker, mistake-free installation insures you are ready-to-go!

New ARC™ (Advanced Radial Curve™) Shifting Technology

Prestacycle introduces UniBlock Pro cassettes with ARC™ Shifting tooth profiles. UniBlock Pro ARC™ is our own unique, all-new shifting profile that provides shifting characteristics equaling or improving upon shifting performance for every major brand. We've performed extensive analysis of all major shifting systems. Our results show that due to how narrow chains have become, chains offer only small differences that contribute to shifting performance. Meanwhile, a great deal of varying technologies exist in cassette tooth profiles from major drivetrain manufacturers creating different specific benefits in one system or another. By examining the demands and benefits required by each particular drivetrain, we've been able to create a new system with the benefits of all drivetrains using one new design, creating all advantages to all systems. Our new design facilitates the fastest, smoothest possible shifting to all systems while minimizing the impact to power delivery.

Going deeper, we've optimized every single tooth pairing on every cassette. A shifting profile from a 16T-to-17T cog is different from a 15T-to-17T cog on a different cassette. These exact-match pairings for both up-and-down shifts provide the highest possible speed and reliability in shifting. Even shifting under load is maximized. Our new Professional cassettes create a new generation of compatibility and enhanced shifting performance.

Warranty and Returns

Cassette Return Policy

Cassettes may ONLY be returned if unopened and in the original, undamaged packaging. Before opening, please review our installation notes shown in this listing. Use of our cassettes outside the operating range of the derailleur manufacturer or outside our recommendations are not covered. Once opened, Prestacycle fully backs Uniblock Pro cassettes with support and a full warranty (see below).

Full Return Policy

We accept returns and exchanges within 30 days of receipt. To make a return, contact Customer Service for an RMA number and return details. All returns must be in original condition, with all original boxes, manuals, parts, plastic bags, and all related packaging. There can be no writing, tape or other objects on the manuals, or product box/packaging. Returned products cannot have any signs of wear, damage, or usage. All UPC codes must be intact; product boxes cannot have been cut or damaged. All returned items must be shipped in a larger shipping box, do not put any mailing labels directly on the product boxes. Shipping charges are not refundable. Use a return shipping method that provides a tracking number and insurance. We do not accept COD or freight collect deliveries. Returns may be subject to a 10% restocking fee. We cannot issue refunds until your return is received and has been inspected for condition.

Warranty

Prestacycle warrants Uniblock Pro Cassettes to be free of defective material or workmanship for one (1) year, and under the conditions stated herein. Warranty is provided only to the original purchaser with proof-of-purchase. Warranty does not cover wear and tear from normal use. Use of our cassettes outside the operating range of the derailleur manufacturer or outside our recommendations are not covered. This warranty is expressly limited to repair or replacement of product found to be defective. Prestacycle assumes no liability for loss due to failure of any product to perform satisfactorily. Prestacycle makes no other warranty, expressed or implied, except that of title. Any and all other warranties are expressly disclaimed.

This warranty applies under conditions of intended use and is exclusive of equipment subjected to: Failure to follow recommended assembly and service procedures, Lack of proper maintenance, excessive duty cycle, exposure to the elements, shipping damage and modification not authorized by Prestacycle. No warranty claims will be honored without prior authorization for repair from Prestacycle. Any replaced or repaired equipment will be warranted for the remainder of the warranty term only.

FAQ's

Q: What drivetrain brands are compatible? 

A: We offer UniBlock PRO cassettes for: 

  • Shimano (10, 11, and 12-speed) 
  • Campagnolo (10, 11, and 12-speed) 
  • SRAM XDR (12-speed) 

Q: How do I know which UniBlock cassette I need? 

A: You need to know three things: 

  • Your drivetrain speed (10, 11, or 12-speed)
  • Your drivetrain brand (Shimano, Campagnolo, or SRAM)
  • Your freehub body type (HG, XDR, Campagnolo, etc.) 

Q: What is a UniBlockPRO Cassette?

A:UniBlockPRO is a single-piece cassette design that provides precise shifting, reduced weight, and easier installation/removal compared to traditional multi-piece cassettes. The entire cassette is machined as one unit for superior performance.

Q: What is an XDR freehub?

A: XDR is SRAM's freehub standard for 12-speed cassettes with smaller 10-tooth cogs. It's slightly longer than standard XD to accommodate road gearing.

Q: How much lighter is a UniBlock cassette?

A: Weight savings vary by model and speed, but the single-piece design typically reduces weight by eliminating spacers and excess material while maintaining strength

Installation Notes

Always adjust shifting for any new Cassette

While Tooth gaps and shifting profiles are optimized for all systems, re-adjustment may be necessary. Various brands of freehubs can cause small variations in cassette positioning.

Confirm Compatibility with your derailleur

Not all derailleurs are compatible with all gear ranges. Please verify if your derailleur is compatible with the largest tooth size, and cog gaps that you are ordering. Electronic shifting systems are the most picky about working with gear ranges not offered by the Original Manufacturer.

Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12-Speed Cassette for SRAM XDR Freehub
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle
Prestacycle UniBlock PRO - 12 - Speed Cassette for SRAM XDR Freehub - Prestacycle

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