Before You Start

Before making any adjustments, set all dials to their middle position. Run any compression lever in the open setting and deactivate all lockouts. This gives you a neutral baseline to work from.

Tools Required

• Shock pump
• Tape measure or ruler
• Multi-tool
• Brand-specific socket
• Notepad and pen
• An assistant (strongly recommended)

You can find our recommended rear shock settings in our specification sheets.

Manufacturer Setup Guides

Download the official tuning guide for your specific fork or shock:

Fox Forks

• Fox 34 Fork Tuning Guide (PDF)
• Fox 38 Fork Tuning Guide (PDF)
• Fox 40 Fork Tuning Guide (PDF)

Fox Shocks

• Fox Float DPS Shock Tuning Guide (PDF)
• Fox Float X Shock Tuning Guide (PDF)
• Fox Float X2 Shock Tuning Guide (PDF)
• Fox DHX2 Shock Tuning Guide (PDF)

Marzocchi

• Marzocchi Bomber DJ / Z1 Fork Tuning Guide (PDF)
• Marzocchi Bomber Z2 Fork Tuning Guide (PDF)
• Marzocchi Bomber CR Shock Tuning Guide (PDF)

X Fusion

• X Fusion 32 Fork Setup Guide (PDF)
• X Fusion O2 Shock Setup Guide (PDF)

Other Brands

• Fox model-specific setup guides (ridefox.com)
• RockShox model-specific setup guides (trailhead.rockshox.com)

Front Fork Setup

Setting Fork Sag

Sag is the amount your suspension compresses under your weight when you're on the bike in a neutral riding position. It should be measured consistently — either standing or seated — every time you make adjustments.

Sag is measured as the distance between the dust wiper and the o-ring on the fork stanchion.

1. Remove the air valve dust cap.
2. Attach the shock pump and note the current air pressure in PSI.
3. Position the bike on flat ground next to a wall, tree, or assistant.
4. Mount the bike in your full riding kit — helmet, pack, water, tools, etc.
5. Balance and lean against your support.
6. Release your brakes.
7. Bounce lightly on the fork to settle the suspension.
8. Move into your neutral riding position.
9. Have your assistant slide the o-ring down to the dust wiper edge.
10. Dismount carefully — do not bounce or load the suspension.
11. Measure the distance between the dust wiper and the o-ring.

Target sag: 15–20% of total fork travel. For a 160mm fork, this is 24–32mm.

• Too much sag → increase air pressure slightly.
• Too little sag → decrease air pressure slightly.

Fox air fork tip: With the shock pump attached, slowly cycle the fork through 25% of its travel 10 times. This equalises pressure between the positive and negative air chambers and will change the reading on the pump gauge. Repeat until sag is correct.

Fork Volume Spacers

Volume spacers change the rate at which the fork ramps up through its travel. More spacers = more progressive feel; fewer spacers = more linear feel.

1. Remove the top cap, count any existing volume spacers, and note the number. Reassemble. Refer to your fork manufacturer's manual for full instructions.
2. Slide the stanchion o-ring up against the dust wiper.
3. On flat ground, ride slowly and bounce/bunnyhop to simulate heavy compression.
4. Step off carefully and measure travel used (distance between dust wiper and o-ring).

Target: 80–85% of travel used.

• Less than 80% used → remove a volume spacer.
• More than 85% used → add a volume spacer.

Fork Compression (High and Low Speed)

Start with compression in the middle setting established at the beginning of this process. High and low speed compression controls how the fork responds to fast impacts (rocks, roots) and slow compressions (braking, corners) respectively. Fine-tune on the trail using the bracketing technique described in the Suspension Testing section.

Fork Rebound (High and Low Speed)

Start with rebound in the middle setting. To find the correct rebound speed:

1. Stand next to the bike on level ground.
2. Quickly and firmly compress and release the fork. Repeat several times.
3. Gradually increase rebound speed (faster) until the front wheel begins to lift slightly off the ground — this is too fast.
4. Slow rebound one click at a time until the wheel stays stable on the ground.

Rear Shock Setup

Setting Rear Shock Sag

Rear shock sag is measured as the distance between the shock dust wiper and the o-ring on the shock shaft, with the rider on the bike in a neutral position.

1. Remove the air valve dust cap.
2. Attach the shock pump and note the current air pressure in PSI.
3. Position the bike on flat ground next to a wall, tree, or assistant.
4. Mount the bike in your full riding kit.
5. Balance and lean against your support.
6. Release your brakes.
7. Bounce lightly on the bike to settle the shock.
8. Move into your neutral riding position.
9. Have your assistant slide the o-ring to the dust wiper edge.
10. Dismount carefully — do not bounce or load the suspension.
11. Measure the distance between the dust wiper and the o-ring.

Target sag: 30% of total shock stroke.

• Too much sag → increase air pressure slightly.
• Too little sag → decrease air pressure slightly.

Fox air shock tip: With the shock pump attached, slowly cycle the shock through 25% of its travel 10 times to equalise pressure between chambers. The gauge reading will change — continue until sag is correct.

Coil shock note: The same sag principles apply. To adjust sag, add or remove spring preload. If significant adjustment is needed, you may need a different spring weight — available from your suspension manufacturer.

Rear Shock Volume Spacers

Volume spacers on the rear shock work the same way as on the fork — more spacers give a more progressive ramp-up.

1. Open the shock to count existing volume spacers. Note the number and reassemble. Refer to your shock manufacturer's manual for full instructions.
2. Slide the shock shaft o-ring up against the dust wiper.
3. On flat ground, ride slowly and bounce/bunnyhop to simulate heavy compression.
4. Step off carefully and measure travel used.

Target: 80–85% of travel used.

• Less than 80% used → remove a volume spacer.
• More than 85% used → add a volume spacer.

Rear Shock Compression (High and Low Speed)

Start with compression in the middle setting. Fine-tune on the trail using the bracketing technique below.

Rear Shock Rebound (High and Low Speed)

Start with rebound in the middle setting. Fine-tune on the trail using the bracketing technique below.

Suspension Testing on the Trail

With your base settings dialled, head to the trails for real-world testing. Choose a short test section (1–2 minutes) that reflects your typical riding. Do this at your usual riding spot — local woods or a bike park.

The Bracketing Technique

Bracketing is a systematic method for finding your optimal settings:

1. Complete a couple of warm-up runs to get a feel for the base setup.
2. Pick one setting (e.g. compression) and adjust 2–3 clicks in one direction.
3. Complete a run and decide: better or worse?
4. If worse, revert to the original setting. If better, adjust another 2–3 clicks in the same direction.
5. Continue until performance gets worse, then step back to the best setting.
6. Work through settings in this order: compression → rebound → volume spacers.
7. If you have separate high and low speed settings, adjust each individually.

Once complete, record every setting along with your weight, the trail, temperature, and conditions. These notes are your baseline to return to if you ever lose your way.

Advanced Suspension Setup

Once you have a solid baseline, advanced setup moves beyond "better or worse" to asking why a change felt different. Return to your test trail with your baseline setup and make one change at a time, noting the effect. Work through every possible setting systematically.

Key variables to consider:

• Trail type and conditions
• Riding goal (speed vs. comfort)
• Bike fit and rider position
• Tyre choice and pressure
• Wheel setup

Remember: the biggest variable is always the rider. Improvements in fitness, skills, and technique will deliver greater gains than any suspension adjustment. Invest in both.

Suspension Servicing

To maintain optimum performance, your fork and shock must be serviced at regular intervals. Service intervals vary by manufacturer and usage — refer to the documentation included with your bike or the manufacturer guides linked above.

Frequently Asked Questions

What is sag and why does it matter?

Sag is the amount your suspension compresses under your weight in a neutral riding position. Correct sag ensures the suspension can both compress and extend through its full travel, giving you grip and control on varied terrain.

What sag should I set on my fork?

For most mountain bike forks, aim for 15–20% of total travel. For a 160mm fork, that's 24–32mm of sag.

What sag should I set on my rear shock?

Aim for 30% of the total shock stroke.

What is the difference between high speed and low speed compression?

High speed compression controls how the suspension responds to fast, sharp impacts like rocks and roots. Low speed compression controls response to slower forces like braking bumps and cornering loads.

What do volume spacers do?

Volume spacers reduce the air volume inside the fork or shock, making the suspension ramp up more progressively towards the end of its travel. More spacers = more progressive; fewer spacers = more linear.

How do I know if my rebound is set correctly?

Rebound is too fast if the front wheel lifts after a compression. Rebound is too slow if the suspension feels packed down and doesn't recover between hits. Aim for the fastest rebound speed at which the wheel stays planted.

How often should I service my suspension?

Service intervals vary by manufacturer and riding intensity. Check the documentation supplied with your bike or the manufacturer's website for specific guidance.

Where can I find the recommended settings for my Saracen?

Saracen's recommended rear shock settings are available in our specification sheets.