Installing Progressive Fork Springs

- Virg


Instructions are for the 1500 Classic & Nomad Drifter is the same

Note: Doing the work is quicker than it took me to write this, so it's really not a big job.

Tools needed:

  1. Some way to take the weight off the front wheel. I use a car jack on each side of the frame, but there are many different ways.
  2. Some small and very small screwdrivers.
  3. Wood dowel or similar "tool", 3/4" diameter
  4. Woodworker's Kwik-Klamp, or a helper One foot of 1" PVC pipe, the strong kind (schedule-40 I believe it's called), very cheap at the hardware store. Go to a small store where they will cut a length for you, the big shopping centers will make you buy a whole 10-foot stick.
  5. Hacksaw to cut the PVC to 4" length.
  6. A very sharp knife to get the Progressive springs out of that ^%#@**!!! factory shrink wrap.


(1) Jack the bike up so the front wheel is slightly off the ground.

(2) Block the front wheel in position so it can't swing around. I put a heavy toolbox on each side of the wheel.

(3) Put a blanket on the tank to avoid scratching by dropped tools, etc.

Now do the following procedures on each side:

(4) Remove the chrome cap from the triple clamp. Careful, it's made of plastic and expensive to replace if it breaks. Pry it out gently with a screwdriver or such.

(5) Press down on the bronze-color plug which you see in the top of the fork tube. I used a thick wood dowel. If you don't have somebody to press down on it for you, a woodworker's clamp can be used to apply pressure. Worked for me.

(6) With the plug down, remove the metal retaining ring, using a very small screwdriver. Careful if you work outside, it might go "sproinnnnggg" away into the blue yonder.

(7) Take the plug out and pull the stock fork spring out slowly. I propped it up in a halfway-out position (just stick a screwdriver into it) and took a 1-hour coffee and cookies break to allow the oil to drain down into the tube. This will save you from remeasuring the oil level, although it would be good to do that.

(8) Remove the old spring. Insert the new spring so that the narrow-wound coils face upward toward the handlebar.

(9) Make a 3-1/2" or 3-3/4" long spacer out of 1"ID. white PVC thich wall pipe available at the hardware store It's cheap. the longer the spacers the more Pre=load you put on the springs, to much and you lose movment of the spring coiles so don't go over board on the spacers.. then read the instructions about how long to cut the spacer and use your riding style to determan how long to make them for your style riding.

(10) Insert spacer on top of the new spring.

(11) Insert plug. Press down on it and insert the retaining ring.

(12) *Very important*! Check carefully to see that the retaining ring is seated properly all the way around.

(13) Put chrome cap back on.


(14) Take the bike off the jacks.

(15) Go for a test ride on a bumpy road and be surprised!

(16) Learn that the remaining limitation on handling are the stock Bridgestone tires. Do preparatory work on the wife (or significant other) explaining the purchase of 2 new aftermarket tires.

For more pre-load on the fork springs, you can experiment with longer spacers. Some in our group have had good results with 4.25" and even 4.5" spacers.

Enjoy your new suspension, and great handling!


here is a little info on progressive rate springs


Progressive Rate Springs

Progressive Rate Springs have many advantages over straight rate springs. For example, if you have a 20lb. straight rate spring it will take 20lbs. of force to compress the spring one inch. Then it will take 20 more lbs. of force to compress it the next inch, and so on, until the end of the travel. A progressive rate spring has the advantage of a rising rate resistance to compression.

for example, a 15lb. to 25lb. progressive rate spring will take 15lbs. to compress it the first inch, then 17lbs. the next inch,
and so on, until the end of the travel: it will take 25lbs. to compress the last inch. The benefit of this is that the spring
can be soft enough at the start of the travel to offer a "plush" ride yet be stiff enough at the end of the travel to soak up the big bumps.


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