ISR Brakes from Sweden are very high quality and rugged systems designed for top racers who demand the best performance and durability from their brake systems.  Race proven, ISR brakes are modular designed to promote easy replacement of individual parts at the racetrack.  This not only saves time but saves you money.  All ISR brake systems are CNC machined from aerospace quality billet aluminum and then finished with a clear coating.  ISR brake systems are a great choice for racing, street, or that custom project.  Available in brake (RH) or clutch (LH) master cylinders and 17.5mm, 15.87mm, or 14mm bores. 


The 21-012 front master cylinder is specifically designed for Supermoto, Street Fighter, or custom motorcycles.  The unique innovative design allows the user to adjust the level of force delivered to the piston by moving the point of contact to the piston.  The design employs a movable lever and fulcrum to apply force to the piston and is adjustable on the fly.  Also incorporated is a completely adjustable lever, the lever distance to the handlebar can be easily adjusted on the fly.  The lever is mounted via a quick change mechanism to facilitate a fast lever replacement in the event of a race crash.  Please Note: The 21-012 family of front master cylinders come standard with the adjustable reach lever. 


Two bore sizes are available, 17.5mm for dual rotor systems or 15.87mm for single rotor setups on brake systems.  Most clutch systems will utilize the smaller bore sizes, like 15.87mm or 14mm.  The 21-012 family of ISR front brake master cylinders have the following specifications:

• 17.5mm bore, 15.87mm, or 14mm bore sizes available
• Clutch or Brake masters available
  
• 10cc reservoir capacity
• M10 x 1.25mm banjo threads
• 0.46kg (1.01lbs) weight
• 5.2:1 - 3:1 leverage ratio adjustment range
• 22mm (7/8") handlebar size

Please Note:  The 14mm bore size is not normal production and is special order only. 

PDF Downloads

ISR 21-012 catalog pages

ISR 21-137 catalog pages