The Yokozuna Ultimo Hy/Mech [paid link] brake set is a hybrid mechanical/hydraulic disc brake system, offering superior modulation and braking power over traditional cable-actuated calipers. Its unique design combines mechanical actuation at the lever with hydraulic power at the caliper, giving riders high-end performance without the need for fully hydraulic levers. This guide walks through installation, adjustment, routine maintenance, troubleshooting, performance optimization, and compatibility concerns for the Ultimo Hy/Mech.
Tools Required
- 5mm and 3mm hex wrenches
- Torque wrench (Nm accurate)
- Needle-nose pliers
- Brake cleaner and lint-free cloth
- Disc rotor truing tool
- Mineral oil brake fluid (Yokozuna-approved)
- Bleed kit (compatible with Yokozuna Ultimo)
- Cable cutters and housing crimper
- Rotor lockring tool (if centerlock)
Installing the Ultimo Hy/Mech Brake Set
Correct installation is essential for optimal performance. The Ultimo caliper features a self-contained hydraulic unit but relies on mechanical cable input from a standard road lever.
Mounting the Caliper
Begin by mounting the caliper to the frame or fork using the included post-mount bolts. Ensure all frame and fork contact surfaces are clean and flat to avoid misalignment. Torque the bolts to 6–8 Nm using a calibrated wrench.
Cable Routing and Housing Setup
Route standard mechanical brake cable housing from the lever to the caliper, ensuring smooth bends and minimal friction. Install compressionless housing for the best lever feel. Use a cable end cap to prevent fraying. Thread the inner cable through the integrated barrel adjuster and anchor bolt on the caliper.
Setting Cable Tension
Apply moderate tension and lightly squeeze the lever. The pistons should engage the rotor with consistent resistance. Secure the anchor bolt to 5–6 Nm. Fine-tune with the barrel adjuster, ensuring lever feel is responsive with minimal dead stroke.
Rotor Installation
Install a 160mm rotor (or size specified by the frame/fork). Ensure it is mounted securely with either 6-bolt or centerlock hardware. Torque to spec and inspect rotor trueness using a rotor tool if needed.
Adjusting the Ultimo Hy/Mech Calipers
After initial installation, fine adjustments ensure optimal braking power and pad alignment.
Pad Alignment and Contact
With the wheel in place, loosen the caliper mounting bolts slightly and squeeze the brake lever firmly to center the caliper. While holding the lever, retighten the mounting bolts to spec. Release the lever and spin the wheel. The rotor should spin freely with no rubbing.
Lever Feel and Modulation
Adjust the barrel adjuster until the brake engages early but does not drag. A well-tuned Ultimo caliper provides a firm lever feel and consistent engagement without sponginess.
Pad Bed-In Procedure
Perform a bed-in process by riding at moderate speed and applying firm, controlled stops ten times. This process deposits an even layer of brake pad material onto the rotor for improved braking power.
Routine Maintenance Guidelines
Proper upkeep ensures long-term performance of the Ultimo Hy/Mech system.
Cable Maintenance
Inspect the inner cable and housing for wear or contamination every 2–3 months. Replace if you notice increased friction, inconsistent lever feel, or visible corrosion.
Caliper Cleaning
Spray the caliper with brake cleaner and wipe down thoroughly with a lint-free cloth. Avoid spraying directly onto the pads. Check for contamination and clean the rotor with isopropyl alcohol.
Brake Pad Inspection
Remove the pads and inspect for uneven wear or contamination. Replace pads when thickness drops below 1mm. Use Yokozuna-compatible pads for best performance.
Hydraulic Fluid Check
Although the hydraulic circuit is sealed, inspect fluid levels and piston retraction behavior every 6 months. If retraction is slow or inconsistent, consider performing a full bleed.
Troubleshooting Common Set-Up Issues
Even a well-installed brake set can develop issues over time. Here are common problems and their resolutions.
Squealing or Noise
Noise often results from pad contamination or rotor glaze. Clean thoroughly and re-bed the system. Ensure rotor is true and torqued correctly.
Inconsistent Lever Feel
This typically points to cable stretch or housing compression. Replace cables if friction is felt. Check for proper cable anchoring at the caliper.
Pad Rubbing
Rotor rubbing may indicate caliper misalignment. Re-center the caliper and verify rotor trueness. Replace warped rotors or misaligned pads.
Weak Braking Power
Weak power often comes from poor pad-to-rotor contact, glazed pads, or insufficient bed-in. Re-bed or replace pads, and verify lever actuation and cable integrity.
Customization and Performance Optimization
The Ultimo Hy/Mech offers room for tuning based on rider preferences and terrain.
Lever Compatibility
Compatible with most road levers designed for mechanical disc brakes. Pairing with high-quality, low-friction cable and housing boosts responsiveness.
Rotor Size Adjustments
For added braking power, consider using 180mm rotors on compatible forks or rear stays. Always match caliper adapters accordingly.
Pad Compound Selection
Choose organic pads for better modulation and quieter operation, or semi-metallic for improved heat management and longevity on descents.
Caliper Spacers and Rotor Shims
If using non-standard rotor thickness or switching wheelsets, spacers can ensure consistent pad contact and avoid dragging.
Comparing the Ultimo Hy/Mech to Similar Brake Systems
The Ultimo stands out in a niche category. Here’s how it compares to peers:
- TRP HY/RD [paid link]: Also a hybrid caliper but bulkier; the Ultimo is lighter and offers better modulation.
- Paul Klamper: Pure mechanical caliper with excellent build quality but lacks the hydraulic boost of the Ultimo.
- Avid BB7 Road: Offers wide adjustability but lacks hydraulic feel. The Ultimo outperforms in power and smoothness.
Compatibility with Other Drivetrain Components
Ensuring smooth integration is key to optimal braking and shifting experience.
Mechanical Levers
Ultimo is compatible with most Shimano, SRAM, and Campagnolo mechanical levers designed for short-pull cable disc calipers.
Rotor Standards
Accepts standard 6-bolt or centerlock rotors; ensure your wheels match the rotor style and mounting standard.
Frame and Fork Fit
Post-mount and flat-mount adapters may be required depending on your frame and fork design. Ensure there is enough clearance for the caliper’s integrated hydraulic reservoir.
FAQs
1. Can I use the Ultimo Hy/Mech with drop bar levers from SRAM or Campagnolo?
Yes, as long as the lever pulls cable like standard mechanical disc systems. The Ultimo is optimized for road lever pull ratios.
2. How often should I bleed the hydraulic portion of the Ultimo caliper?
In most cases, bleeding is only needed if braking feels spongy or if the caliper shows signs of internal air contamination. Inspect annually or as needed.
3. Can I use aftermarket pads with the Ultimo Hy/Mech?
Yes, but it’s best to use Yokozuna-specific pads or verified compatibles to ensure pad retention and braking performance remain optimal.
4. What’s the advantage of the hybrid system over full hydraulic?
The hybrid design allows riders to use traditional mechanical levers while still benefiting from the increased power and modulation of hydraulic calipers.
5. My caliper leaks fluid—what should I do?
This indicates a failed internal seal. Stop using the brake immediately and contact Yokozuna for servicing or replacement.
6. Do I need a rotor size adapter when changing rotor diameters?
Yes. Always use the correct adapter when moving from 160mm to 180mm rotors or vice versa. Match the adapter to your frame/fork mount type.
Conclusion
Servicing the Yokozuna Ultimo Hy/Mech brake set yourself is entirely feasible with the right tools and care. This hybrid system combines mechanical simplicity with hydraulic power, offering impressive braking without full-hydro system complexity. Proper setup, routine maintenance, and careful alignment ensure your Ultimo brakes remain powerful, quiet, and consistent ride after ride.