UniBlock PRO Cassette (12 Speed) (Shimano)

Prestacycle UniBlock Pro 12-speed cassettes deliver smoother shifting, greater freehub engagement and long-term durability through a single-piece design and ARC™ shifting technology. Engineered for maximum compatibility and performance, they reduce wear, improve power transfer and simplify installation across modern and legacy drivetrains.

• Greater Freehub Engagement, Smoother Operation
  Single-block construction spreads load across the entire freehub in every gear, reducing wear, lowering rolling resistance and protecting high-end alloy freehubs.
• Spacer-Free Design
  No loose cogs or spacers means faster cleaning, quicker installation and zero risk of incorrect assembly.
• ARC™ Advanced Radial Curve Shifting Technology
  Optimised tooth profiles deliver fast, smooth, reliable shifting across all major drivetrain systems, including under load.
• Optimised Tooth Pairing
  Each shift ramp and tooth profile is matched for both upshifts and downshifts to maximise speed and consistency.
• Wide Gear Range Availability
  Available for Shimano 12-speed road in 11-25, 11-28, 11-30, 11-32, 11-34, 11-36 and 11-40 options.
• Cross-Freehub Compatibility
  Enables use of one freehub across different drivetrain systems, including HG wheels on Campagnolo setups.
• Backwards & Future Compatibility
  Supports fitting 11 and 12 speed systems to Shimano 10 speed wheels (with optional lockring) and adapting newer drivetrains to older wheels or trainers.
• HG12 Freehub Interface
  Compatible with HG12, HG11 and HG10 freehubs. Wider contact surfaces increase engagement despite fewer teeth.
• Performance Optimised Chain Pairing
  Designed to work with YBN 12-speed chains for fastest, most accurate shifting and lower rolling resistance.
  

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

— COMPATIBILITY —

• GEARS: 12 Speed
• SHIFTING: Shimano
• YBN 12 speed chains recommended for optimum shifting performance 
• FREEHUB: Shimano HG11 AND the new HG12!
  (also fits HG10 with our HG10 Lockring, not included)
  

— 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
• Red alloy locknut included

Use a shifting optimized chain

Unlike all other drivetrain systems, Shimano's 12 speed Road Hyperglide+ system moves the shifting optimization away from the chain and onto their Cassettes. It's a great running system within a narrow gear range - meaning - even Shimano stopped selling their Dura-ace 11-28 cassette after the first year. The Shimano chain itself has the thickest side plates in 12 speed with NO apparent design for shifting function.

We recommend YBN, SRAM or Campagnolo 12 speed chains for optimum shifting performance. YBN Chains are our favourite because they use the same stronger Chrome Molybdenum Steel as our cassettes which offers thinner, lighter, faster shifting and with longer life. Please Note: Use of these recommended chains will improve shifting even on Shimano Brand Cassettes, meaning that our recommendation supports interchangeability.

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.

Note: Shimano 12 speed Di2 recommended gear ratios are 11-30, 11-32 and 11-34. 

Limit screw settings can vary with any cassette / wheel change

DI2 installation instructions may suggest “one full turn” of the limit screws past the limit. We have found this negatively affects the shifting of any brand cassette as it controls the range for each shift. We highly recommend setting the limits screws to offer no-more-than regular free operation of the min/max gears.

Optional Cassette spacer is included

Prestacycle 11 and 12 Speed Cassettes include a 1mm spacer which can optionally be used to move the cassette farther from the spokes. Different wheelsets, different brands of hubs, variations with custom built wheels using different construction, the spacing of the derailleur hanger and many more factors can all determine if the spacer is needed, optional or specifically should not be used.

Reasons to use this spacer:

• The Chain/derailleur is too close to the spokes when in the largest cog
• The gear range is outside of the derailleur min/max range
• Moving the cassette outward improves the bike's chainline
• Moving the cassette outward makes it more compatible with wheel swaps

Reasons to NOT use this spacer:

• The spacer pushes the freehub engagement off the end of the freehub
• The gear range is outside of the derailleur min/max range
• You are using our optional lockring to put 11/12 speed on a 10 speed wheel
• The smallest cog is too close to the frame's chainstay or rear dropout

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.

This product can expose you to chemicals including Nickel (Metallic), Lead, Diisononyl Phthalate (DINP), Urethane (Ethyl Carbamate), 1,3-Butadiene or Styrene, which is known to the State of California to cause cancer or reproductive harm.

For more information, go to www.P65Warnings.ca.gov.

Prestacycle Statement:

• Products made with Stainless or Plated Steel contain Nickel (Metallic).
• Products made with Brass contain Federally accepted trace amounts of Lead.
• Most soft Plastics including Vinyl contain Diisononyl Phthalate (DINP) .
• Buna Rubber contains1,3-Butadiene and Styrene.

Prestacycle manufactures it’s products with these materials as they are the highest standard available to manufacture these products to suit their purpose. Prestacycle does not dispute any of the findings made by California or the Federal Government. The health and safety of our customers is very important to us. We will always take every step possible to insure our products are as safe as possible.