by: Traveler

This spring change is the result of months of research and post-reading. It increases the spring force by about 30% both front and back. My impression of the whole change is that it feels tighter, more cohesive, and more stable. My FZ1 now feels like it has 'matched components' for the combined weight. It will hold a better line in turns, and it reduced squat and dive.

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Front Springs Replacement

I replaced the stock front springs with part number FS 37 x 315 x 1.0kg. from Traxxion. A procedure was included and I'll refer to it as Traxxion Procedure.

Special Tools needed for this job: vise grips, pipe cutter, metric ruler, FZ1 tool kit

1) Remove Front Wheel and Fender

Pat's Page (Front Wheel Removal) or see Service Manual (page 4-3)

I ran out of duct tape, so alternatively, I hung the brake calipers with tie wraps to the blinkers.

2) Remove Forks

See bigworm1's fork upgrade procedure or see Service Manual (page 4-48).

Or, simply - loosen upper triple clamp bolts so the fork cap isn't locked, then crack the fork cap bolt loose, do not remove it. To drop the forks out, loosen the lower triple clamp bolts - support the fork when doing this, don't let it freefall.

3) Disassemble Fork Spring Assembly

  1. Drain Fluid: Now that the fork is out, holding fork upright, remove cap bolt. Drain nasty old fork oil into suitable container. No need to remember that smell because your garage (or living room for some of you) will smell like that for a few days.
  2. Use a 14mm wrench for the lock nut, and a 17mm wrench for the fork cap - release the lock nut from the fork cap. The fork cap bolt should then screw off the damper adjusting rod easily by hand. The O-ring should remain with the fork cap bolt. The locknut will still be holding the spring seat, spacer, and fork spring compressed. (It is OK if the locknut and all slide down into the inner tube. You can reach a middle finger into the fork tube and pull up the damper rod by the locknut or later by the threads.)
  3. To remove the locknut can be a bit tricky, although mine was easy. An extra set of hands might be helpful. While pulling up on the damper rod threads, compress the spring using the spacer or spring seat enough to take force off of the locknut, then unscrew the locknut by hand. (This is where they recommend a special tool to hold the damper rod while removing the locknut, I didn't need it. Serv. Manual Pg. 4-48).

4) Measure and Cut New Spacer (for external top-out spring forks)

  1. If you trust my math and have 315mm long springs, then cut two equal spacers 81mm long, then skip to Section 5).
  2. The new spring requires a new spacer. The stock spacer was 65mm and the new spacer length needs to be determined by measuring "ZERO PRELOAD" + 15mm. This is basically the amount of free space needing to be filled +15mm.
  3. Setup_1: Set the fork upright, add new spring, washer, and spring seat. Measurement_1: measure the distance from the top of the fork tube, to the top of the resting washer (this is Figure 4A in the Traxxion procedure). I measured 116mm.
  4. Setup_2: Get the fork cap bolt assembly. Back the PRELOAD ADJUSTER all the way out. Measurement_2: Measure from the bottom of the preload adjuster to the to the bottom edge of the top lip of the fork cap. (this is Figure 4C in the Traxxion procedure). I measured 50mm.
  5. Do the math: Measurement_1 - Measurement_2 + 15mm = length of spacer. In my case, 116mm - 50mm + 15mm = 81mm. Cut two equal spacers from the supplied stock. De-burr the new spacers with a file and make the contact surfaces smooth.

5) Add Fork Oil

  1. I used 1 bottle of Golden Spectro 85/150 fork oil (about 11$ at the local cycle shop). This is the lighter weight oil, my preference.
  2. Allow the fork tube to compress fully, then add new fork oil.
  3. Bleed the air out: Pump the damping rod slowly up and down a few times until there is no SKIP felt in the stroke. This is to purge the air from the system.
  4. Fill the fork to 5.5 inches from the top. One method: overfill slightly then draw out the extra using a straw marked at 5.5 inches. Another method: clamp vise grips on a ruler or measure perpendicular to 5.5 inches, then place on top of fork tube - using it like a dip stick.Add or subtract as needed to get 5.5 inches or 140mm.

6) Assemble New Fork Spring Assembly

  1. Prepare the Fork Cap Bolt for re-assembly: Back the PRELOAD ADJUSTER all the way out if not already done. Traxxion Procedure: Preset the rebound dampers by turning the REBOUND ADJUSTER all the way out to the last 'click', then in 3 full turns, always stop on 'clicks'. This will ensure both rebound adjusters will have the same adjustment range. See Traxxion's procedure for more detail on this.
  2. Basically, reverse steps 3, 2, 1 from Section 3 above. Install the spring, spring seat, spacer, washer. I used my middle finger to reach into the fork tube and pull the thread of the damper rod up. You could tie a long string to it and feed things on slowly, or just work quickly - pull the rod up, slip the spring on before the rod falls down too far, then grab the rod again.
  3. Once the spring, washer, spacer, and spring seat are on - compress the spring so you can thread the locknut all the way down to the stops. This is to allow enough thread for the fork cap bolt to fully seat on the damper rod. I wish I had taken better pics!
  4. Thread the fork cap bolt onto the damper rod until it stops. Then use the locknut to lock the fully-seated fork cap bolt in place (18ft-lb). The PRELOAD ADJUSTERS should still be all the way out. This will ensure both forks have equal preload settings.
  5. Carefully compress and thread the fork cap bolt into the fork tube. Do not torque it yet, wait until it is mounted in the triple clamp. Take a break, check the FZ1OA message board for new "what is the best windscreen' posts, answer them accordingly.
  6. Should look like this.

7) Re-Install Forks

Again see bigworm1's fork upgrade procedure or see Service Manual (page 4-51).

Basically, insert fork cartridges, align surface fork cap with surface of triple clamp (per the manual), or align the mark on the fork tube (1.5mm lower) with the surface of the triple clamp (the way my FZ was from the dealer). Tighten lower and upper as needed to install fender and front wheel. Pump the forks a few times (procedure on Pat's site - Pat's Page (Front Wheel Removal) if desired. Torque lower triple clamp bolts to 17ft-lb, cap bolt to 18ft-lb, upper triple clamp bolts to 22 ft-lb. Finish all other front wheel related torques.

8) Set Sag and initial settings

I measured the sag using a zip tie and the surface of the lower triple clamp. I got 35mm right off the bat - perfect according to the Traxxion procedure. That was with the preload still all the way out, so I turned it a few hairs to get it off the hard stop and left it there at about 4.5.

Initial settings: my recommendations are - preload 4, compression damping 8, and rebound damping 10.This was a 30% increase in spring force.

Rear Spring Replacement

I replaced the stock shock spring with a spring, part number SSH 7" x 550lb. from Traxxion.

Special Tools needed for this job: Coil Spring Compressor Tool ITEM 3980-0VGA Harbor Freight has them for $9.99. There should be a store near you also. Retail Stores Also a 15/16" combination wrench for that coil spring compressor tool.

I had the rear wheel OFF doing this, but I don't think you need to, so I'll skip the rear wheel part.

1) Remove Shock Absorber Assembly Service Manual Section (4-63)

  1. Remove front Connecting Arm Bolts and back Connecting Arm Bolts.
  2. Remove Relay Arm Bolt.
  3. Support swingarm/wheel before the next step, it will drop when the rear shock lower bolt is removed.
  4. Remove rear shock LOWER bolt.
  5. Remove rear shock UPPER bolt.

2) Remove old Spring and Install New Spring

  1. Choose your technique: This is where there are many ways to compress a spring to remove it (send it out, local shop, special tool, vise,...). I chose the $10 tool from Harbor Freight. I had to modify the tool with a cut-off wheel attached to my drill.
  2. Adjust the preload to minimum. Compress the spring until the retaining ring can be removed.
  3. Once the retaining ring is removed, the spring can be uncompressed, then it will slide off.
  4. Thread new spring onto the shock assembly first, then compress the new spring until the retaining ring can be installed. Maintain the minimum PRELOAD setting to make it easier.
  5. Install retaining ring.Uncompress the spring.

3) Install Rear Shock Assembly

  1. Grease spacers and bearings and metal to metal contact points. Also, I put a little grease on the PRELOAD adjustment mechanism to make it easier to move back and forth.
  2. Install rear shock UPPER bolt (29ft-lbs).
  3. Lift swingarm/wheel, the install rear shock LOWER bolt (29ft-lbs).
  4. Install Relay Arm Bolt (29ft-lbs).
  5. Install front Connecting Arm Bolts and back Connecting Arm Bolts (29ft-lbs). I think all of these bolts are inserted from the shift lever side, so the nuts are on the brake lever side.

8) Set sag and Initial settings

I haven't measured sag yet, because it is so involved. Initial settings: my recommendations are for a 180lb. rider: preload - position 2 (1 click from minimum), compression damping 7, and rebound damping 8. This was a 34% increase in spring force.

Email me if you have any corrections, questions, suggestions: Email Traveler

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The information contained here is for entertainment purposes only. No information presented here is to be relied upon for issues of rider safety nor to replace the services of a qualified service technician. Any attempts to follow or duplicate any of these procedures are done so completely at your own risk. By reading the information on this site, you agree to assume complete responsibility for any and all actual or consequential damages that may arise from any information presented herein.