Tutorial: Adjusting the Shock Spring Preload for the RX3

[SpudRider]

The spring preload setting of the shock absorber in the RX3 produces a very harsh ride. Fortunately, adjusting the spring preload allows this shock to perform much better.

Remove both saddles from the bike, and remove the black plastic panel which covers the battery on the right side of the bike.

To adjust the shock spring preload, you must raise the rear wheel from the ground to remove the bike's weight from the shock absorber. If you have a center stand, lift the bike onto it, and weight the front of the bike to raise the rear wheel from the ground.

I don't have a center stand. Therefore, I place the side stand of my RX3 on a brick, which almost raises the bike to a vertical position. I then turn the front wheel to the left, and place my Husky 3-Ton jack under the center stand support on the right side of the motorcycle. Pumping the jack lever raises the rear wheel off the ground, and places the bike in a very solid, secure position.

[SpudRider]

Remove the rear wheel so it was not weighting the shock absorber, and to enable yourself to gain better access to the shock itself. To protect the brake caliper and brake line, secure the rear brake caliper to the swingarm with a piece of Romex wire.

[SpudRider]

The locking ring for the shock spring has a single Allen bolt which tightens it. You adjust the spring preload either by turning the spring itself, or by turning the locking ring, which sits above the spring at the top of the shock. You don't need a special tool to tighten the spring preload. To gain access to the locking ring and the Allen bolt, remove the battery and the battery box from the motorcycle.

First, remove the battery. Then remove the evaporative canister which is attached to the bottom of the battery box.

[SpudRider]

However, before you can remove the battery box itself, you need to gain access to one of the four bolts securing the battery box, which is partially covered by the upper side panel at the rear of the bike. Remove the screw at the back of the side panel, and remove the bolt securing the right side of the passenger hand grip. This will allow you to pop the side cover panel from its rubber grommet. With the panel loose, tilt it clockwise, which will allow you to remove the final bolt which secures the battery box.

After removing all four bolts, remove the battery box, which allows full access to the locking ring of the shock spring.

[SpudRider]

Using a socket wrench and an Allen key adapter, loosen the locking ring. Moving aside the mud flap, grab the shock spring with your left hand. Kneeling beside the bike, also grab the shock spring with your right hand.

Turning the spring counter-clockwise for three revolutions of the locking bolt, you should completely loosen the locking ring. This will verify the shock has been set at the minimum spring preload.

After verifying minimum spring preload, tighten the spring for three revolutions of the locking ring, returning the spring to its original setting. Then tighten the spring for an additional, three complete revolutions, to increase the spring preload. Next, tighten the Allen bolt, which secures the locking ring in place.

[SpudRider]

Having adjusted the spring preload, replace the battery box. Then, attach the evaporative canister to the bottom of the battery box. Replace the battery. Then return the side cover panel to its original position. Finally, replace the wheel. Lower the bike from the jack or center stand, replace the black panel covering the battery, and replace both saddles. With the bike fully assembled, you are ready to take a ride to test the shock absorber with the increased spring preload.

Repeat this entire procedure, either tightening, or loosening the shock spring preload, until the shock absorber performs as you desire.

[Weldangrind]

I presume that six full turns from zero preload is about right for a 200+lbs rider; is that correct?

[SpudRider]

Originally Posted by Weldangrind

I presume that six full turns from zero preload is about right for a 200+lbs rider; is that correct?

I would guess six full turns from the stock position, which is minimal preload, would be about right for a rider who weighs 200 pounds. Unfortunately, I weigh more than I should, so I am going outside shortly to add another 3 turns to the spring preload on my RX3. This setting will bring me nine full turns from the minimal preload position.

I haven't added all the luggage, and the crash bars, to my RX3. Therefore, I might need to adjust the spring preload some more, after I finish adding all the equipment. However, it is much easier working on the bike in its current 'naked' configuration. I suggest riders sort out the suspension on this bike before they add all the luggage, et cetera.

[katflap]

Great tutorial Spud, Thanks,

Now for a dumb question

Being a beginner at suspension adjustment

What is the " ride feel " I'm after for when it's set right.

or is it one of those things that can't be explained

Spotted another difference CSC / Honley, no evaporation canister for us (UK)

[SpudRider]

Originally Posted by katflap

Great tutorial Spud, Thanks,

Now for a dumb question

Being a beginner at suspension adjustment

What is the " ride feel " I'm after for when it's set right.

or is it one of those things that can't be explained

Spotted another difference CSC / Honley, no evaporation canister for us (UK)

Thank you, Kat.

You want the suspension to feel smooth. You don't want to feel any harshness or jarring when you encounter potholes, or bumps in the road or trail.

I will take more photos of the connections to the evaporation canister when I check the valve lash. It doesn't weigh much, and it doesn't block access to anything, but I am still considering removing it.

[pete]

did you measure the sags before adjusting the shock
to give you a idea where you need to be heading
or if you can get the correct setting with the standard spring
for your weight..

what you should be after is
35mm Static Sag. "bike under it's own weight"
33% - 1/3 of suspension travel , Rider Sag.. "Rider on bike"




.

[SpudRider]

Yes, I did measure the static sag. I'm waiting for my friend to help me measure the rider sag. However, I think those measurements apply more to dirt bikes, than adventure bikes. Also, in this particular instance, this shock absorber seriously needs to be adjusted to achieve the best results, irregardless of the 'ideal' numbers.

[pete]

Road bikes set for
10mm static & 20% rider
so if you set somewhere in the middle
of road & dirt you could be about right...

Be a Soft road set up or a hard dirt set up...

[AZRider]

I used a shock spanner wrench and jacked the bike up to lift the rear wheel as Spud suggested. It was a bit fiddly, but I was able to make 3 full turns in a few minutes without removing anything.

[SpudRider]

Originally Posted by pete

did you measure the sags before adjusting the shock
to give you a idea where you need to be heading
or if you can get the correct setting with the standard spring
for your weight..

what you should be after is
35mm Static Sag. "bike under it's own weight"
33% - 1/3 of suspension travel , Rider Sag.. "Rider on bike"

.

That's the way I set up the shock preload on my other bikes, Pete. I used that method when I installed a stronger spring on the XT225 shock absorber of my Zongshen ZS200GY-2. I also used that method after I installed lowering links on both my Honda XR650L, and my Honda CRF250X.

I wanted to use that method on my Zongshen RX3, but my good friend who has helped me in the past was unavailable for about a week. The RX3 shock absorber is soft enough in stock configuration to be punishing at times. Also, it was set for the minimal spring preload, so I decided to experiment with the spring preload while I waited for my friend to find time to help me.

Because of the limited suspension travel, and the adventure/street bike characteristics of the suspension, I decided to adjust the spring preload for the best riding response on pavement and dirt while I waited for my friend to help me perform the traditional method.

I believe I have optimized the shock preload as best I can for the stock equipment, but the shock performance is still not satisfactory. I suspect either the limited suspension travel (5.6 inches) is not adequate for dual purpose riding, or, most probably, the stock shock spring is not strong enough for my weight.

Therefore, I am going to keep the current settings until my friend finds time to help me employ the traditional, proven method.