Author Topic: ZRX Front End Upgrade for the Concours - by Randy Forsland  (Read 5455 times)

Offline elvin315

  • Administrator
  • Full Member
  • *****
  • Posts: 140
  • Country: us
edited by elvin rivera

MotoGP Paddock Girls - (Laguna Seca GP) (The video's owner prevents external embedding)

Not a Connie fork but very pretty.

NOTE: This procedure is for the pre 94 (early) models. The mod can be done on post 93 (late) models also, but the steps will be slightly different.


Parts Needed
  • ZRX upper and lower triple clamp with bearings, seals, and handlebar clamp.
  • Left and Right fork tube assemblies.
  • ZRX front fender (I used a fender from a ZX6R with modified mounting brackets).
  • ZRX handlebar or any 7/8 inch tubular bar that suits you.
  • ZRX front wheel with 310 mm rotors and tire.
  • ZRX Front axle with spacer and speedo assembly.
  • Left and right ZRX brake calipers.
  • ZRX brake lines with banjo bolts and new crush washers (stainless steel aftermarket preferred).

Preparation for ZG Front End Removal
  • Put the bike on its center stand. Use a jack under the engine to raise the front wheel off of the ground.
  • Remove the front fairing. This is not absolutely necessary but it will make the job easier. There is some grinding that needs to be done on the head stem tube to allow for proper clearance of the ignition switch.

ZG Front End Removal
  • Unscrew the speedometer cable from the gear box on the left side of the front wheel.
  • Place an aluminum foil cake pan under the front calipers to catch any brake fluid that leaks out.
  • Remove the 12mm banjo bolts from both of the brake lines on the front calipers. Remove the brake lines and let them drain.
  • Remove the two allen bolts (A) from each of the calipers. (Figure 1)
  • Remove both caliper assemblies.
  • Remove the front wheel.
  • Remove the front fender and fender mount.
  • Remove the bar end weights from both sides of the handlebar.
  • Remove the grip from the left (clutch side) handlebar.
  • Remove the banjo bolt (A) and brake line from the right handlebar reservoir assembly. (Figure 2)
  • Loosen the two upper clamp bolts from the brake lever.
  • Loosen the two screws on the right switch housing until it will slide freely.

fig.1 fig.2

  • Remove the two handlebar mounting bolts (C) and loosen the clamp bolt (B). (Figure 3)
  • Remove the right handlebar assembly and slide the brake lever and switch lever/throttle assembly off of it.
  • Repeat for the left handlebar but do not remove the banjo bolt and clutch line from the clutch reservoir assembly. (Figure 4)
  • Release air pressure from the forks.
  • Loosen the upper and lower fork clamp bolts and the connecting pipe clamp screw on the left fork.
  • With a twisting motion, work the fork leg down and out.
  • Repeat for the other fork tube.

fig.3 fig.4

  • Loosen the two screws and remove the steering stem head cover.
  • Remove the stem head nut and washer from the upper triple clamp.
  • Remove the upper triple clamp assembly.
  • Using a Torx socket, remove the two screws holding the ignition switch in place. If no Torx socket is available, the screws will need to be drilled out.
  • Take off the lock washer and remove the steering stem locknut.
  • Remove the upper bearing cap.
  • Remove the lower triple clamp assembly.
  • Remove the upper tapered roller bearings.
  • Clean the old grease from the upper and lower bearing races.

Prep for ZRX Front End Installation
  • Locate the handlebar lock stop. It is the triangular shaped protuberance that is located on the steering stem tube near the front of the upper bearing race. (Figures 5 & 6)
  • Grind the lock stop flush with the steering stem tube.
  • Grind about ¼ inch of material from the front fairing stay and the fairing stay mounting post as shown in Figure 5. This is necessary to allow for ignition switch clearance as the switch now sits about 1 inch lower than stock. An alternative to this is to relocate the ignition switch. No grinding of the lock stop of fairing stay is necessary if you choose to relocate the ignition switch.
  • Prime and paint all exposed metal surfaces.

fig.5 fig.6

ZRX Front End Installation
  • Grease the new tapered roller bearings.
  • Insert the lower triple clamp with lower bearing cap and bearings into the steering stem tube.
  • Install the upper bearing and grease seal.
  • Install the upper bearing cap.
  • Install the stem locknut so that the recessed edge is facing down. Tighten the locknut so that there is no excess steering stem play.
  • Install the ignition switch on the upper triple clamp.
  • Install the lock washer, upper triple clamp, washer and nut. Do not tighten the nut at this time.
  • Slide the left fork tube through the lower and upper triple clamps.
  • Tighten the lower triple clamp bolts just enough to prevent the fork tube from falling out. The top of the fork should be flush with the upper triple clamp.
  • Repeat for the right fork tube.

Under-view of ZRX top clamp > ZRX top clamp >

  • Torque the stem head nut and triple clamp bolts to factory specifications.
  • Install the front fender.
  • Install the front wheel, spacer, speedo drive, and axle.
  • Install the left and right brake calipers.
  • Re-attach the speedometer cable to the speedo drive.
  • Slide the left and right handlebar switch assemblies and levers onto the ZRX handlebar.
  • The front halves of switch assemblies have a small projection that locks them onto the handlebars and prevents them from rotating. Fit the projection (A) into the small holes (B) on each side of the handlebar. (Figure 4).
  • Tighten the switch assembly screws and the lever clamp bolts.
  • Mount the handlebars on the lower handle bar clamp.
  • Install and tighten the upper handle bar clamp.
  • Install the left grip and bar end weights.
  • Install the new brake lines to the brake reservoir and the calipers.
  • Bleed the brakes according to the instructions supplied with the new lines.
  • Ensure that the steering moves freely from stop to stop with no binding or cable/wiring restrictions. Adjust as necessary.
  • Lower the front end back onto the ground. Set preload and damping as needed.
  • Take the bike out for a test spin and readjust steering stem locknut tightness if it is too loose or too tight.

fig.7 fig.8

NOTE: One caveat to consider is this. The steering lock will no longer function after this modification is made. This could be remedied by welding a new steering lock stop directly above the front fairing stay mount on the steering stem tube.