Hope RX4+ SL Flat Mount Complete Caliper - DOT Version

HOPE RX4+ SL Flat Mount - 4-piston power for road and gravel
Hope's benchmark caliper evolves to become the RX4+ SL. Entirely CNC-machined from a 2014 T6 aluminium block, this caliper combines exceptional lightness with increased structural rigidity. Its monobloc design eliminates the "fuzzy" lever feel to offer surgical braking precision, even on the longest descents.

Why upgrade to the RX4+ SL (DOT Version)?

The RX4+ SL caliper uses 4 phenolic resin pistons of different diameters (2x14mm and 2x16mm) to guarantee perfect modulation and consistent braking power. This version is specifically designed to work with DOT 4.0 or 5.1 brake fluid, making it perfectly compatible with SRAM Road/Gravel groupsets.

What's new in the SL version:

• Slimline Design: New bore caps reduce the overall width of the caliper, offering better compatibility with the most compact modern frames and forks.
• Simplified Maintenance: New bleed screw compatible with SRAM fittings or Hope bleed tools (HTTBLRXDOT syringe - specific - available separately).
• Mounting Versatility: This Flat Mount (34mm spacing) standard can be installed on both front and rear. It allows the use of 140, 160, or 180mm rotors when using dedicated adapters (HBMX, HBMY, or HBMZ).

Key features:

• Monobloc CNC machining: 2014 T6 Aluminium for optimal thermal dissipation.
• Pads included: Delivered with two types of pads (Blue for road use, Red for CX/Gravel).
• Customisation: Available in 7 Hope anodised colours (Black, Silver, Red, Blue, Purple, Orange, Smoke).

Specifications

• CNC-machined 2014 T6 aluminium monobloc caliper
• 4-piston caliper (two 14mm and two 16mm pistons)
• Standard Flat Mount (34mm bolt spacing)
• Compatible rotor diameters: 140mm, 160mm, or 180mm (with adapters)
• Compatible braking system: DOT only
• Colour: Black, Blue, Red, Orange, Silver, Smoke, or Purple
• Reference: HBSPC109

Lever compatibility:

• SRAM Red / Red eTap AXS
• SRAM Force / Force eTap AXS
• SRAM Rival / Rival eTap AXS
• SRAM Apex
• SRAM S900

In the box

• RX4+ SL brake caliper (Standard Flat Mount)
• Blue pads for Road use
• Red pads for Cyclo Cross/Gravel use
• Hydraulic fittings: copper washer, brass insert and olive, shroud nut
• Bleed pad spacer

Documentation:

Guide to determining which RX4+ caliper you need
Guide to determining which adapter you need
RX4+ SL caliper exploded view

Pro tip: Ensure you use exclusively DOT 4.0 or 5.1 fluid. The use of mineral oil would irreversibly damage the seals of this version.