A good electric mountain bike doesn’t just come down to motor choice and battery size. Setup matters — a lot. Because e-MTBs are heavier and often ridden for longer, small setup errors can turn into big problems: harshness on repeated hits, vague steering on wet roots, rear-end wallow on climbs, or a bike that feels “busy” and tiring instead of planted and confidence-inspiring.

The aim of this guide is to give you a solid baseline suspension setup for an e-MTB, using simple steps you can do at home with a shock pump and a bit of patience. We’ll cover the three essentials most riders need: sag, rebound, and tyre pressures. If you get those roughly right, your bike will feel safer and more predictable, you’ll get more grip, and you’ll waste less energy fighting the bike — which, on an e-MTB, can also help battery range.

This is written for typical UK riding: mixed trail surfaces, wet weather, roots, rocks, trail-centre features and natural bridleway terrain. It’s not about chasing “pro” settings. It’s about making your e-MTB feel calm, controlled and enjoyable.

(Internal links to add: How to get more range from your e-MTB battery, Hardtail vs full-suspension explained, and your future Tyres for UK e-MTB riding guide.)

What you need before you start

You don’t need a workshop. The basics are:

A shock pump (for fork and rear shock), a tape measure or sag o-ring (most forks/shocks have one), and a notepad/phone to record settings. Ideally, do your setup wearing the kit you normally ride in — including a hydration pack if you usually carry one — because weight changes sag.

If your suspension has multiple adjustments (high/low-speed compression, climb switches, etc.), don’t worry. You can get 80% of the benefit from sag and rebound alone. Compression and “platform” settings can come later once the bike feels balanced.

Step 1: Set sag (the foundation)

Sag is how much the suspension compresses under your body weight when you’re in a normal riding position. It’s the baseline that determines where in the travel you ride most of the time. Too much sag and the bike can feel wallowy, vague and prone to bottoming out. Too little sag and it can feel harsh, skittish and lacking grip.

Recommended e-MTB sag targets (starting points)

These are good baselines, not laws:

• Fork (hardtail or full-suspension): around 20–25% sag
• Rear shock (full-suspension): around 25–30% sag

If you’re riding very technical terrain and prioritise traction and comfort, you’ll usually sit towards the higher end. If you prioritise support and pumping through trail features, you might sit slightly lower. For a first setup, aim for the middle.

How to measure and set fork sag

1. Make sure the fork is fully extended.
2. Slide the o-ring down to the fork seal (or use a zip tie loosely).
3. Get on the bike and adopt a neutral standing position (hands on bars, feet level, light bend in knees and elbows).
4. Carefully step off without compressing the fork again.
5. Measure how far the o-ring moved. Divide that by total travel to get sag percentage.

Example: 30mm sag on a 150mm fork = 20% sag.

If sag is too high, add air pressure. If sag is too low, remove air pressure. Repeat until you hit your target.

How to set rear shock sag (full-suspension)

1. Slide the shock o-ring to the seal.
2. Sit on the bike in a normal seated position, then stand neutral for a moment (some bikes settle differently).
3. Step off carefully and measure o-ring movement.
4. Convert to percentage using shock stroke (some shocks list stroke on the body; otherwise look up your bike’s spec).

A crucial note: rear shock sag can be sensitive to body position. Be consistent in how you load it each time.

Step 2: Set rebound (control vs “pogo”)

Rebound controls how quickly the suspension returns after compression. Too fast and the bike can feel bouncy and unstable, especially on repeated hits. Too slow and the suspension “packs down” — it doesn’t recover between bumps — which makes the bike ride lower in its travel and feel harsh and dead.

Most suspension has rebound adjusters at the bottom of the fork leg and on the shock. They’re usually click-based.

The simple rebound method that works

Start with the manufacturer’s recommended setting if you have it. If not:

1. Turn rebound all the way slow (usually clockwise) until it stops. Don’t force it.
2. Count clicks all the way to fast (usually anti-clockwise).
3. Set it back to the middle.

Now refine:

• If the bike feels like it’s kicking back, skipping, or “pinging” off roots, slow rebound slightly (a few clicks).
• If the bike feels like it’s stuck down, harsh on repeated bumps, or can’t recover between hits, speed up rebound slightly.

A quick car-park test

With the bike stationary, push down hard on the bars to compress the fork, then let it return. It should return quickly but not “top out” with a clunk or bounce past its resting point. Repeat for the rear on a full-suspension bike by pushing on the saddle.

This test isn’t perfect, but it catches extremes.

Step 3: Tyre pressures (the UK grip lever)

If there’s one setup change that can transform an e-MTB in UK conditions, it’s tyre pressure. Too high and you’ll slide on wet roots and chatter across rough ground. Too low and the bike feels draggy, vague, and risks rim strikes or burping (tubeless) — plus it can hurt range.

There’s no universal correct pressure because it depends on rider weight, tyre casing, rim width, trail conditions and whether you’re tubeless. But you can get a strong baseline quickly.

Starting pressures (tubeless, typical trail tyres)

As a rough starting point for an average rider on modern trail tyres:

• Front: ~ 20–24 psi
• Rear: ~ 23–28 psi

General rules:

• The rear normally runs a bit higher than the front.
• Heavier riders need higher pressures.
• Tougher casings can be run slightly lower without squirm.
• Wet roots often reward slightly lower pressures for conformity and grip — within reason.

The two-ride method (best approach)

Set a starting pressure, then go ride a familiar loop.

• If grip is poor and the bike feels harsh/deflecty, drop 1–2 psi.
• If the bike feels vague, squirmy, or you hit rims on rocks, add 1–2 psi.

Record what you changed. Repeat once more. After two rides you’ll have a much better baseline than any internet recommendation.

Balance front-to-rear: the “feels like one bike” goal

A well-set-up e-MTB feels balanced: the fork and shock work together, the bike doesn’t pitch forward under braking, and it doesn’t feel like the rear is riding low or the front is too tall.

Signs your bike is unbalanced:

• Front dives too much under braking: reduce fork sag slightly or add a touch of compression (if available), or increase front tyre pressure marginally.
• Rear wallows on climbs: reduce rear sag slightly, check rebound isn’t too slow, and ensure shock pressure is correct.
• Rear feels harsh despite correct sag: rebound may be too slow and packing down; check tyre pressure and casing too.

If you’re on a hardtail, the “balance” comes from fork sag/rebound plus rear tyre pressure. Many hardtails feel better with careful attention to rear tyre choice and pressure because that’s your only rear “suspension”.

What about compression, tokens/volume spacers, and fancy settings?

Compression controls how easily the suspension compresses under load. If your fork/shock has a simple compression dial, start in the middle. If it has multiple circuits (high/low speed), leave them at recommended settings until sag, rebound and tyre pressures feel right.

Volume spacers (tokens) affect end-stroke support — how readily you bottom out. If you’re regularly using full travel harshly even with appropriate sag, tokens can help. But don’t chase this too early. Many “bottom-out” complaints are actually caused by rebound problems or tyre pressures that are too high, leading to deflection and harsh hits.

Your baseline checklist (save this)

For a first proper setup session, you want:

• Fork sag: 20–25%
• Shock sag (if applicable): 25–30%
• Rebound: start at midpoint, then adjust in small steps
• Tyre pressures: start sensible, then tune in 1–2 psi steps
• Record: pressures + rebound clicks so you can always return to baseline

Once that’s done, ride the bike and only change one thing at a time. It’s the fastest way to learn what each adjustment does.