5.1 KYB 36, 37, 38, 40mm

    Cupped-Top

    Anti-Dive Brakes

    Kawasaki, Suzuki, Yamaha

Suzuki version


1984 Kawasaki GPz750 Turbo

Most KYB Anti-Dive Forks are brake actuated hydraulically. Emulator installation disables the Anti-Dive. It does not matter if the hydraulic brake hardware is either removed or left intact. It will be disabled by the location of the compression feed holes.

The use of proper rate springs and Emulators eliminates the need for Anti-Dive and improves the ride quality significantly.

A stock damping rod is pictured below. There are 2 or 4 small diameter compression holes below the step near the bottom of the rod.

Modification is largely the same as cup-top damping rods as outlined in the Standard Emulator Instructions. The difference is the additional compression holes MUST be located above the step in order to bypass the anti-dive unit. Otherwise the forks will be quite harsh.

 

84 GPz750 Turbo - This version has Air-Assist and normally runs air pressure. It has two top-out springs, one that is very soft. This requires more spring preload than a standard top-out spring. See your DVS Setup Sheet for recommendations.

Modify the Damping Rod - Add Compression Feed Holes

Starting at 6mm above the step, drill a total of:

  • Six 6mm (1/4") compression feed holes - for 17mm and smaller diameter rods
  • Six 8mm (5/16") compression feed holes - for rods larger than 17mm

Add holes in 10mm increments with each set of 2 holes perpendicular to the last to maintain rod strength.

Deburr the holes inside and out.

Do not bother modifying the holes below the step.

 

Many models do not have the second soft top-out spring.

Wave Washers
The damping rod is stepped at the bottom to retain the bottoming cone. The bottoming cone acts as a check valve. On compression it forces the oil out and through the Anti-Dive valve. On rebound it opens, pushing against the wave washers, and refills the bottom chamber.

Pay attention to their order. There are two wave washers and one flat washer. The order should be "wave, flat, wave".

 

Follow the Standard Emulator Instructions

Install the assembly into the fork leg from the top.

  1. Install the Top-out Spring on the Damping Rod.
  2. Install the wave washers and bottoming cone.
  3. Install the Lower Fork Leg and tighten the bottom bolt.
  4. Setup the fork spring preload.
  5. Remove the spring and install the fork fluid.
  6. Install the fork spring. Re-check the preload to insure the Emulator is seating properly (not cocked).
  7. Install the fork cap.
It is a good idea to inspect the sealing o-rings in the Anti-Dive unit. Make sure the surfaces are flat. Install new o-rings and re-install.
Block-Off Plates - optional
The Anti-Dive is completely bypassed with the addition of the new compression feed holes.

You have 3 choices:

  1. Leave the brake lines intact.
  2. Leave off the brake line connectors and plug them.
  3. Install Block-off Plates. There are companies that have made block-off plates. If you are fabricating a block off plate you must make sure it seals.