Brake HAYES Dominion A4, black-purple, limited edition

Dominion A4 | black-purple | limited edition

This limited edition purple HAYES Dominion A4 brakes can only be seen on HAYES sponsored riders such as Rémy Metallier, Hannes Klausner, Pat Smage, Ali Clarkson, Clemens Kaudela and Jordi Bago. The purple colour is a reference to the early days of MTB cycling, when HAYES brought to the world a technology that changed our sport forever.

You can only buy the limited edition Dominion A4 in black and purple once a year and once it sells out, you'll have to wait until next year!

Brake lever

• brake lever body is made of forged aluminium alloy
• Ergonomic aluminium brake lever with a very soft step thanks to the roller bearings
• the end of the lever is fitted with small dimples at the end for firm contact between the gloved finger and the lever surface
• the lever can be combined with adapters for attaching the gearshift directly to the brake lever sleeve
• the lever can be used on the left or right side of the handlebar (flip-flop)
• the lever can be removed from the handlebars without removing the grips or the shifter
• precision engineered and tested hydraulic axial system using DOT 5.1 brake oil
• Brake lever piston has a conical seal and a special slip ring to reduce friction
• the HAYES Dominion A4 brake lever can be adjusted for the distance between the lever and the handlebars (by turning the wheel on the end lever)
• with the HAYES Dominion A4 brake lever it is possible to adjust the dead lever step using a 2mm inbus key (by default the shortest possible step is set)
• the HAYES Dominion lever has been designed to have the shortest possible deadstroke - i.e. the time without the onset of brake power (pad and disc contact)
• the fluid reservoir is large so that there is no risk of air entering the system even with significant pad wear

Brake caliper

• the caliper is made of cold forged aluminium
• the caliper is made of two separate pieces and connected by two large screws
• further increase in the strength of the caliper is provided by the locking screw of the plates called King Pin
• The HAYES Dominion A4 caliper is a 4-piston caliper, i.e. it contains a set of 4 independent pistons
• the large 17mm pistons give the brake high performance in all situations
• the pistons are made of lightweight aluminium alloy to ensure rapid heat transfer to the caliper from where it is then transferred to the surrounding area
• the pistons are fitted with a square (in cross-section) seal, which has specific elastic properties to maintain perfect retraction even at high pad run-out
• the caliper is equipped with an expansion spring between the brake pads
• the pads are secured in the caliper by a locking screw (HAYES King Pin)
• the caliper is supplied with semi-metallic brake pads T106 (installed in the brake caliper), but also sintered pads T100
• this is a version of the pads that is joined into one via 2-pistons on each side
• WARNING: the pads must be run in before use, or the bed-in process (repeated running and smooth braking)
• swivel banjo brake hose connection, which allows the hose to be directed away from the caliper and towards the wheel
• post mount or PM mounting of the brake caliper
• detailed adjustment of the caliper and alignment to the disc is possible by means of small worms on the post mount (crosshair system)
• M6 screws for mounting the caliper to the frame or fork (using an inbus wrench) are also included
• precision engineered and tested hydraulic system using DOT 5.1 brake oil
• Two-Stroke bleed port system allows you to bleed separately without having to pull fluid through the lever

Brake hose

• brake is supplied with Kevlar hydraulic hose HAYES K8 with inner diameter (ID) 2.5mm outer diameter (OD) 5.5mm
• the length of the unshortened hose is 1800mm or 1000mm (your choice)
• parts for shortening the hose to the desired length are also included (1x hose insert / 1x hose olive)

Recommended rotor

• combine the brake with HAYES D-Series brake discs
• Recommended discs are available in 160, 180, 203 and 220mm diameters

Weight

• weight of whole brake is 310g (including 1000mm hose lenght and M6 tightening bolts, without rotor)

Package includes

• 1x brake HAYES Dominion A4
  • lever + hose + caliper / filled and ready for immediate use
• 1x HAYES hose olive
• 1x HAYES hose insert
• 2x M6 bolt (inbus 6mm) for tightening of the caliper on fork / frame
• 2x washer below M6 bolt
• 1x HAYES manual
• 1x HAYES transportation insert
• 1x HAYES bleed block with integrated caliper piston cleaning and lubrication system
• 1x semi-metallic brake pads HAYES T106
• 1x metallic brake pads HAYES T100

Shiffter adapters (not included)

• brakes can be combined with SRAM or SHIMANO shifter mounts (it is necessary to buy HAYES adapters directly)

Important information

Read the manual supplied with each brake carefully for correct brake installation!

Video - HAYES Dominion brake technical informations

Video - HAYES Dominion brake - installation

Video - HAYES Dominion brake - hose shortening

Video - HAYES Dominion brake - standard bleeding procedure

Video - HAYES Dominion brake - caliper Two Port bleeding procedure 

Video - HAYES Dominion brake - caliper piston cleaning and lubrication

Video - HAYES Dominion brake - change of the lever blade

Video - HAYES Dominion brake - change of the brake pads