The Yokozuna Ultimo Hy/Mech [paid link] brake set represents a hybrid advancement in braking technology for road cyclists, combining the mechanical simplicity of cable-actuated systems with the power and modulation benefits of hydraulic braking. Designed with a focus on improving braking efficiency and control, this system is suitable for riders upgrading from mechanical disc brakes without adopting a full hydraulic system. This guide covers everything from installation and adjustment to optimization, troubleshooting, and compatibility.
Design and Functional Overview
The Ultimo Hy/Mech calipers are a hybrid hydraulic design—mechanically actuated by standard brake cables but hydraulically driven at the caliper end. This configuration allows cyclists to retain their existing mechanical levers while gaining hydraulic-level braking performance. Internally, the caliper features an integrated master cylinder that amplifies force upon cable pull, resulting in stronger, more controlled braking with less hand fatigue.
Key materials include a forged aluminum caliper body for strength-to-weight efficiency and ceramic pistons that resist heat build-up during prolonged descents. Yokozuna’s proprietary hydraulic internals are pre-bled from the factory, making them a user-friendly upgrade.
Tools Required
- 5mm and 2.5mm hex wrenches
- Torque wrench with Nm scale
- Rotor truing tool (if necessary)
- Caliper alignment shim or business card
- Clean rag and isopropyl alcohol
- Compatible rotor (160mm or 140mm depending on frame)
Installation Instructions
The Ultimo Hy/Mech calipers come ready for flat mount or post mount, depending on your frame and fork configuration. Begin by securing the rotor to the hub with the correct torque spec (typically 6-8 Nm).
Mount the caliper using the appropriate adapters if needed. The mounting bolts should be torqued to 6-8 Nm. Insert the cable into the caliper’s actuation arm and secure it with light tension. Avoid over-clamping, as the arm is finely machined and requires only enough tension to engage the piston assembly.
Align the caliper using either visual centering or a business card shim method. This step is critical to avoid rotor rub. Tighten the caliper bolts evenly once centered.
Adjustment Techniques
To achieve optimal braking, adjust cable tension using the inline barrel adjuster or the lever’s cable adjuster. Proper tension results in a responsive lever feel without excessive free stroke. Fine-tune piston centering by loosening the caliper bolts slightly, squeezing the brake lever, and retightening while holding the lever engaged.
Pad clearance can be adjusted internally via a small hex screw located on the caliper. If the pads are too close and cause drag, a half-turn counterclockwise can increase clearance. If braking feels weak, turn it clockwise slightly to bring the pads closer.
Routine Maintenance
Maintenance for the Ultimo Hy/Mech is relatively straightforward due to its sealed hydraulic circuit. Periodically inspect the pads for wear—replace them when thickness drops below 1mm. Yokozuna uses Shimano-style pads for easy sourcing.
Clean the rotors and calipers with isopropyl alcohol to prevent contamination. If brake feel deteriorates over time, check the cable condition. Replace frayed or corroded cables, and lubricate housing with light grease to ensure smooth actuation.
Bleeding is not typically necessary unless there’s a loss of hydraulic pressure. For service users comfortable with hydraulic systems, the Ultimo can be re-bled using standard mineral oil-compatible tools.
Troubleshooting Common Issues
Rotor Rub: This usually stems from caliper misalignment. Re-align using the lever squeeze method or shim technique. Also inspect rotor for warping.
Spongy Lever Feel: Often caused by cable stretch or contamination. Inspect cable housing and lever pivot points for grime and lubricate accordingly. Bleeding may be required if the internal system has air bubbles.
Weak Braking Power: Could indicate pad contamination or glazed surfaces. Clean or sand pads, and clean the rotors thoroughly. Replace pads if necessary.
Uneven Pad Wear: Usually due to improper caliper centering. Re-align caliper and ensure pistons move symmetrically during actuation.
Performance Optimization Tips
For riders demanding maximum performance, consider upgrading to compressionless housing for better cable efficiency. These housings reduce cable squish, translating more of your lever force into piston actuation.
Use high-quality rotors that match Yokozuna’s recommended specifications. Lightweight rotors may reduce braking consistency under heat. Also, choosing sintered or semi-metallic pads based on riding style (wet vs dry conditions) can drastically improve braking consistency.
Experiment with pad compound and rotor size combinations. On steep descents or in touring applications, a 160mm rotor up front may yield better results.
Customization Options
Although not designed for visual customization, the Ultimo Hy/Mech does allow for functional tuning:
- Swap stock pads with aftermarket options like Kool-Stop or SwissStop for tailored bite and modulation.
- Replace stock cables with high-performance kits such as Jagwire Elite Sealed or Yokozuna Reaction cables.
- Combine with high-leverage mechanical levers like TRP RRL or Cane Creek for enhanced force output.
Compatibility Overview
The Ultimo Hy/Mech is fully compatible with most road mechanical brake levers, including SRAM, Shimano, and Campagnolo. It is crucial to match rotor sizes with frame and fork clearance. Post-mount and flat-mount frames are both supported via adapters.
Pads are Shimano-style (B01S-compatible), providing a wide selection of aftermarket choices. However, not all flat-mount adapters offer perfect alignment, so always test before final tightening.
Housing should be low-friction and compressionless for best results. Hydraulic hose systems are not needed, making this a plug-and-play solution for mechanical lever users.
Model Comparison
When compared to TRP HY/RD [paid link] and Juin Tech F1, the Ultimo Hy/Mech stands out in terms of lever feel and modulation. While HY/RD systems often feel spongy due to internal mechanical conversions, the Ultimo offers a more direct lever engagement.
Juin Tech’s F1 brakes are lighter but lack the stopping power of the Ultimo under aggressive use. Yokozuna’s focus on piston quality and internal fluid mechanics gives it the edge in long descents and heavier rider setups.
Who Should Choose the Ultimo Hy/Mech
The Ultimo Hy/Mech is ideal for riders upgrading from mechanical disc brakes but not ready for full hydraulic conversion. It’s particularly suited for:
- Cyclists using vintage or rim brake-style mechanical levers.
- Riders seeking improved modulation and power on a budget.
- Long-distance tourers needing field-serviceable braking systems.
Its ease of installation and low maintenance needs make it suitable for home mechanics as well.
Frequently Asked Questions (FAQs)
Q1: Do I need hydraulic levers for the Ultimo Hy/Mech?
No, it works with standard mechanical levers from most major brands.
Q2: Can I use this brake with carbon rims?
No, this is a disc brake system and is not compatible with rim brake setups.
Q3: Is bleeding required after installation?
No, the system comes pre-bled. Bleeding is only needed if performance declines or during pad piston servicing.
Q4: What pad types are compatible?
The Ultimo uses Shimano-style B01S pads. Organic, semi-metallic, and sintered pads are all compatible.
Q5: Does it support 180mm rotors?
Yes, if your frame and fork are rated for that size and you use the correct adapters.
Q6: Is this brake good for gravel bikes?
Yes, the Ultimo performs well on gravel due to its strong modulation and consistent stopping power in varied terrain.
Conclusion
The Yokozuna Ultimo Hy/Mech brake set offers a unique balance of mechanical simplicity and hydraulic power. With its user-friendly setup, consistent performance, and broad compatibility, it’s a top-tier choice for cyclists seeking an upgrade without the complexity of full hydraulic systems. Whether you’re commuting, racing, or adventuring, the Ultimo delivers reliable braking with minimal fuss.