How to adjust a walking pad or treadmill belt

How the rear roller bolts work

At the back of the pad, the rear roller is held by two bolts, one each side, usually reached through small holes in the end caps. Turning a bolt clockwise moves that end of the roller back and tightens the belt on that side. Turning it anticlockwise loosens that side.

Tension is set by turning both bolts by the same amount. Tracking, or centring, is set by turning one bolt relative to the other. Most makers describe it this way, but a few reverse the direction or use a different design, so check your manual.

Before you start

• The Allen key supplied with the pad, or the size given in the manual
• A level floor; check with a spirit level or phone app if the belt keeps drifting
• Clear space behind the pad so you can reach the bolts
• A note of how many turns you make on each side

Note:Unplug the pad and remove the safety key while you turn the bolts. Only run the belt to check tracking with nobody on it, keep hands, hair, loose clothing and cables clear of the rollers, and stop it before adjusting again.

How to centre the belt

1. 1

   Unplug the pad. Look at the gap between the belt edge and the frame on each side.

2. 2

   Identify which way it drifts. If the belt has moved towards the left side, you will adjust the left bolt.

3. 3

   Turn the bolt on the side the belt has drifted towards clockwise by a quarter turn.

4. 4

   Plug in, start the belt with nobody on it and run it at about 3 km/h for one to two minutes.

5. 5

   Stop the belt and unplug again, then check the gaps.

6. 6

   Repeat in quarter turns until the gaps are even. Avoid large turns, as the belt reacts slowly.

How to set belt tension

A belt that is too loose slips or hesitates when your foot lands. A belt that is too tight puts extra load on the motor and rollers and wears them faster. Many manuals suggest that you should be able to lift the belt edge at the middle of the deck by a few centimetres. Your manual may give a specific figure.

To tighten, turn both rear bolts clockwise by the same amount, a quarter turn at a time, then test by walking slowly. To loosen, turn both anticlockwise. If the belt still slips after tensioning, the deck may be dry; see how to lubricate a walking pad and treadmill belt slipping.

Checking the result

After centring and tensioning, walk at a slow speed for a few minutes and watch the belt. Then stop, unplug and recheck the gaps. Your walking can shift the belt slightly differently from an empty run, especially if you walk off-centre or favour one foot. Small final tweaks are normal.

If the belt keeps drifting however you adjust it, check the floor is level, check the pad is not twisted on a thick or uneven mat, and look at the belt edge for wear. A belt that is worn, stretched or damaged may need replacing by the maker or a repairer.

When to call the maker

For pads that list belt sizes and maintenance details, see the best walking pads and the best under-desk treadmills.

• The belt edge is frayed or the belt is torn.
• A roller grinds, clicks or feels rough.
• The bolts reach the end of their travel and the belt is still loose.
• The pad is under warranty and the manual says not to adjust it yourself.

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Frequently asked questions

Which way do I turn the bolt if my treadmill belt drifts left? On most models, turn the left rear bolt clockwise a quarter turn. Check your manual, as some differ.

How tight should a walking pad belt be? Tight enough not to slip, but loose enough that the edge lifts a few centimetres at the middle. Your manual may give a figure.

Why does my belt keep going off centre? An uneven floor, walking off-centre, a soft mat or uneven tension. Level the pad and adjust in small steps.

Can I adjust the belt while it is running? Only with nobody on it and with great care. It is safer to stop, unplug, adjust and then test.