How to adjust your MTB’s suspension

Whether you ride a hardtail, full-suspension bike, a classic MTB or an e-MTB – only with the right suspension setup can you unlock the full potential of your bike. Even small adjustments noticeably improve both comfort and performance.

Before you start, get a few essentials ready: a shock pump, a hex key or multitool, a measuring tape or ruler, and a small O-ring or zip tie as a marker. This makes the suspension adjustment much easier.With just a few simple steps you can then tune your fork and shock so your bike climbs more efficiently, descends with more control – and guarantees more confidence and fun on the trails.

In the second step, you first release the air from fork and shock. Remove the valve cap and attach the shock pump straight onto the valve to avoid damaging the thread. Then let all the air escape from both fork and shock.

Next, push the O-ring on the stanchion down to the dust seal. If there is no O-ring, you can use a loosely fitted zip tie as a marker. Compress fork and shock one after the other by pressing firmly on the handlebar until they reach the end of their travel.

Now use the shock pump again and fill in about 50 PSI of air. This allows fork and shock to slowly extend again. Always refer to the manufacturer’s recommended air pressure values as a guideline.

In the fully extended position, measure the distance between the dust seal and the O-ring. Write down the values for fork and shock, then slide the O-ring back down to the seal.

Now it’s time to set the SAG – the negative suspension travel. This is the part of the suspension that compresses only under your body weight when you sit on the bike.

How to measure the SAG:

• Sit on your bike in a normal riding position – not too far forward, not too far back. Use a wall or a helper for support.
• If you usually ride with a backpack, wear it now and load it realistically.
• Slide the O-ring (or a loosely fitted zip tie) up against the dust seal on the shock. Carefully dismount without sudden movements, so the reading isn’t affected.

Now calculate your SAG value:
Measured negative travel ÷ maximum travel × 100 = SAG in percent.

Reference values:

• Cross Country / Marathon: 20–25 %
• All Mountain / Trail: 25–30 %
• Enduro: 25–35 %
• Freeride / Downhill: 30–40 %

Less suspension travel (XC/Marathon) means a smaller SAG. More suspension travel (Enduro/Freeride) usually requires a larger SAG.

On many SIMPLON bikes you’ll find a scale on the shock that makes reading the SAG easier. Otherwise, simply adjust the air pressure step by step until you reach the recommended value.

Final check: Compress the rear suspension again by pushing down firmly. If the O-ring stays in place and doesn’t slip off the stanchion – you’re good to go.

In this step you set the rebound damping. Rebound controls how quickly the fork and shock extend again after being compressed. Like compression damping, it is regulated by an oil circuit inside the suspension.

The basic rule: the heavier the rider and the stiffer the suspension, the more rebound damping you need.

How to test the rebound setting:

• Put your full body weight onto the fork and then release it suddenly.
• The suspension should extend quickly, but not so fast that the front wheel leaves the ground.
• Repeat the same test on the rear shock.

Work your way step by step until you find the right setting.

Your basic suspension setup is done. Now it’s time to ride and fine-tune. Choose a short but representative test trail – ideally with a climb, some root sections, and a few small drops or jumps.
Important: Always change only one parameter. If you adjust rebound, compression or air pressure one after the other, you’ll immediately notice which change has which effect.

The principle is the same for MTBs and e-MTBs. Because of the higher overall weight, e-MTBs often need slightly more air pressure, but the suspension setup process itself is identical.

Want to go further? Check out our advanced guide on the perfect suspension setup, where we explain fine-tuning options like volume spacers and detailed compression settings.

And if you’re still unsure: your local dealer can help you dial in the perfect suspension setup.