KustomTech Brake Master Cylinders

KustomTech brake master cylinders from the Deluxe line bolt to the handlebar and drive the front brake. Every body is cut from a solid block of aluminium or brass, then polished, brushed or anodised by hand. The lever gets the same treatment, so the whole unit reads as one part rather than an assembly.

Picking the bore of your KustomTech brake master cylinder

The bore sets the feel. A small diameter gives a long travel and a soft pull, which is reassuring in town. A large one firms the lever up and shortens the stroke, which suits four-piston calipers. Each listing states the figure, in inches and in millimetres.

25.4 or 22 mm handlebar?

Measure your bar before ordering. Most Harley-Davidson models run 25.4 mm, while Japanese-based builds often stay at 22 mm. Clamps exist in both sizes, so nothing forces you to change handlebars.

Fitting and upkeep

The fitting takes a standard braided hose. Plan a full bleed after mounting, then a fluid level check every six months. DOT 4 suits the whole range. Finally, moderate torque is enough: machined aluminium does not like excessive tightening.

Brake or clutch?

Some bodies also drive a hydraulic clutch. The displaced volume is not the same, so check the stated use on the listing before ordering. A brake unit fitted to a clutch gives a hard lever and an incomplete stroke. If you are unsure, send us your slave cylinder reference and we will confirm the match before you buy.

These 13 references belong to the KustomTech custom motorcycle parts range. See also the external master cylinders. Official dimensions are published on the Kustom Tech website.