General

The FXDX model features rear shock absorbers that can be adjusted for rebound damping and five spring preload positions.

The front suspension uses cartridge valve 39 mm forks that adjust for compression, rebound damping and spring preload.

The front and rear suspension preload setting will need to be adjusted for your weight and should be made before the motorcycle is ridden any distance. Your Harley-Davidson dealer can assist you in setting this when you take delivery of the motorcycle.

If the preload adjustment is correct and you have the rebound and compression damping set at the factory recommended points, the motorcycle should ride properly.
If these preload adjustment settings are unsatisfactory, they can be changed.

WARNING

Adjust both shock absorbers equally. Improper adjustment can adversely affect stability and handling, which could result in death or serious injury. (00036b)

NOTE

Evaluating and changing the rebound and compression damping is a very subjective process with many variables and should be approached carefully.

Damping is set at the factory for the average rider under normal riding conditions. Preload adjustment settings can be adjusted to compensate for individual riding styles, weight variations or when carrying a passenger.

Definitions

Damping: Resistance to movement. Damping affects how easily the suspension can move and limits oscillations of the system once movement has begun.

Compression: Suspension is compressed when the wheel moves up.

Rebound: The suspension is rebounding when it is moving back from being compressed.

Preload: The spring is compressed somewhat during assembly. This initial compression provides a loaded condition in the spring. This initial compression is referred to as preload.

Spring Preload

Front and rear suspension spring preload must be adjusted before any other adjustments can be attempted. This adjustment assures that the suspension has the proper amount of travel.

Spring preload is the most important suspension adjustment offered on your FXDX motorcycle. Correct setting of preload will result in a motorcycle that suits the rider's size and weight.

NOTE

Two people are needed to carry out spring preload adjustments.

1.	Take the motorcycle off the jiffy stand and bounce the back end up and down a few times to be sure the suspension is free and unbinding.
2.	See Figure 1. With the motorcycle unloaded, take the following measurements. a. At the rear shock, measure the distance A, from the upper shock bolt center to the lower shock bolt center. b. At the front fork, measure the distance B, from the front axle center to the bottom of the upper triple clamp.
3.	With the help of an assistant take the same measurements with the rider in full gear on the motorcycle. NOTE The assistant should help balance the motorcycle so the rider can keep both feet on the footpegs.
4.	Bounce a few times on the seat to be sure the suspension is free and not binding.
5.	Subtract the second measurement from the first. The difference, which is the squat, must be in the range of 0.5-1.0 in. (12.7-25.4 mm). If it is not, adjustment is necessary.
	WARNING Be sure both shock absorber adjusting cams and front fork spring adjusting nuts are adjusted to same preload positions. Improper adjustments can adversely affect stability and handling, which could result in death or serious injury. (00037b)
6.	To adjust rear shock spring preload turn spring adjusting cam to the desired position with a spanner wrench. A spanner wrench (Part No. 94700-52C) for this purpose is available from your Harley-Davidson dealer. See Figure 2. NOTE Changes in load will require changes in the preload setting. Carrying less weight than was used for setting up the suspension will require a reduction in the preload. Increasing the load will require an increase in the preload.
7.	To adjust front preload turn mechanical preload adjusting nut with a 7/8 in. wrench. Always observe lines on cylindrical portion of adjusting nuts to keep adjustments equal on both forks. a. Turn clockwise to increase preload b. Turn counterclockwise to decrease preload.

Figure 1. Preload Measurement: Dyna Models

Figure 2. Spanner Wrench

Front Compression and Rebound

WARNING

Be sure compression and rebound damping settings on fork legs are identical. Improper adjustments can adversely affect stability and handling, which could result in death or serious injury. (00038a)

Make all suspension adjustments in one or two click increments. Adjusting more than one or two clicks at a time may cause you to skip the best adjustment.

Test ride after each adjustment. When an adjustment makes no difference, return to the previous adjustment and try a different approach.

See Figure 3. The fork compression damping adjuster has 14 click positions. Equal adjustments are made to the adjuster knobs at the base of each fork leg.

Rotating the adjuster in the "H" direction (clockwise) gives a harder setting.
Rotating in the "S" direction (counterclockwise) yields softer damping.

Located on top of each fork leg, the fork rebound adjuster knobs have 14 click positions. Make adjustments by counting the clicks while turning the adjuster knob(s).

Turning the adjuster knobs clockwise until they lock yields maximum rebound damping. Forks set in this position will have the slowest rebound.
Adjusters turned fully counterclockwise will have the least amount of rebound damping. This adjustment will produce the fastest rebound.

1	Compression damping adjuster
2	Mechanical preload adjusting nut
3	Rebound damping adjuster
4	Factory preload: 4 lines visible, 5th line flush with top of slider cap

Figure 3. Front Suspension Adjustments: FXDX Models

Rear Suspension Adjustments

Make all suspension adjustments in one or two click increments. Adjusting more than one or two clicks at a time may cause you to skip the best adjustment.

Test ride after each adjustment. When an adjustment makes no difference, return to the previous adjustment and try a different approach.

See Figure 4. Adjust rebound damping by using the dial below the upper shock eye. There are 15 click positions for the rebound damping adjuster.

Rotate toward "H" clockwise to increases rebound damping.
Rotate toward "S" counterclockwise to decrease rebound damping.

NOTE

Rotate adjusters to full clockwise (position 1) or maximum hard position first, then back off to desired setting.

If the preload adjustment is correct and you have the rebound damping set at the factory recommended points the motorcycle should handle and ride properly. If these settings are unsatisfactory, they can be changed.

1	Rear shock absorber
2	Rebound damping adjuster screw
3	Preload adjusting cam

Figure 4. Rear Shock Absorber: Dyna Models

Adjustment Guidelines

To achieve the proper settings you will need the preload adjusted properly, the tires inflated properly and a familiar bumpy road. It is useful if the road contains a variety of different kinds of bumps.

Refer to Table 1. Begin the process by putting all the damping adjustments at the factory recommended settings and riding the motorcycle over a variety of surfaces and bumps at different speeds. If the suspension is set properly the motorcycle will be stable and comfortable.

If you are not satisfied with the factory settings refer to Table 2. This information should help you achieve settings that suit your riding style. Remember, any setting chosen is a compromise.

Table 1. Factory Recommended Suspension Settings: Dyna Models

ADJUSTMENT	SETTING*
Fork rebound	Position 8
Fork compression	Position 3
Fork preload	See illustration
Rear shock compression	N/A
Rear shock rebound	Position 3
Rear shock preload	Third cam step
All settings from maximum hard.

Table 2. Suspension Adjustment Guidelines

CONDITION	ADJUSTMENT SOLUTION
Bike wallows through turns.	Increase rebound damping.
Feels loose or vague after bumps.
Wheel tends to "pogo" after passing over a bump. This is noticable by watching the bike continue to bounce as it travels over multiple bumps.
Wheel responds to bump, but doesn't return to ground quickly after bumps. This is more pronounced over a series of bumps and is often referred to as "packing down."	Reduce rebound damping.
The bike bottoms out or dips while corning.	Increase compression damping.
Bike has excessive brake dive.	Increase preload.
Harsh ride particulary over washboard surfaces.	Reduce compression damping.
Bumps kick through handlebars or seat.	Reduce preload.
Suspension seems not to respond the bumps. This is evidenced by tire chattering (a movement with short stroke and high frequency) through corners or by jolting the rider over rough roads.	Reduce preload.