How to adjust a treadmill belt

Is your treadmill belt slipping ?


Treadmill belt running to one side?

Learn how to adjust the treadmill belt properly.

Its dangerous to run on a slipping treadmill belt so follow these few steps and exercise safely.

Firstly how do you know when your treadmill belt is slipping? Well, when your feet come down on the treadmill it will feel like the belt is stopping for a split second. You will feel unsteady and feel like you could easily lose balance.  It can cause you to fall or become unstable (physically). This can be very dangerous and if you fall on your treadmill it will very easily graze your skin and spit you out the back of your machine. This is no way to exercise. You can have us service your treadmill  which in most cases will have your treadmill running a lot smoother and will help prolong the life of your treadmill. Or you can have a go yourself.

Step 1

Ensure your hair or clothing can’t get caught in the treadmill rollers or belt. Be very careful as treadmills can cause serious injuries if you get your hair, fingers or clothing caught in the rollers. If you need to tie your hair back make sure you tie it properly. If your hair falls unexpectedly it’s more dangerous than not lying it back at all. I’ve seen the results of someone getting their fingers caught in a rear roller of a treadmill and both her arms were fulling bandaged. If you handy with tools and you want to service your own fitness equipment by all means,  just take care.

Step 2

Make sure your treadmill has been lubricated between the treadmill belt & deck. Lack of lubrication can cause the belt to grab on the deck momentarily causing the belt to slip on the rollers. Check out my articale on how to lubricate your treadmill . It’s very easy to lubricate your treadmill an it will prolong the life of your machine.

Step 3

Walk on the treadmill at about 4 km/h and try and stop the treadmill running belt with your foot. If the belt is loose it will stop while the motor and front roller keep turning. To see what’s slipping you will need to remove the treadmill motor cover. Make sure you fully unplug the treadmill as there’s 230-volt mains power under there. Make sure you unplug the treadmill as opposed to just flicking the switch off at the wall. When the treadmill is unplugged you can see at a glance there is no power going to it. Once you have removed the treadmill motor cover you can plug the treadmill back in. Restart the treadmill and if  you try to stop the treadmill running belt with your foot and the roller stops with your belt then the treadmill motor drive belt or the front roller pulley is probably the problem.

When the treadmill belt is tensioned properly it will slip for a second and then grab .

Step 4

If your treadmill belt is to one side you will need to address that first. Crouching behind the treadmill you will see an end cap either side of the running belt. They will have holes in them normally with allen head bolts , one in each end cap. Most are allen head bolts and need a 6mm allen key to adjust. Some are 5mm and some are phillips head screws. 

On the side that the belt is running over to , turn the bolt clockwise to tighten 1/4 of a turn at a time. Then I would start the treadmill and walk on the opposite side of the belt pushing it over to the middle. I would then let it run without me on it and see if it stays in the middle. I would keep repeating this step until the belt stays in the middle. Run the treadmill for a few minutes at 4 km/h and check that the treadmill running belt stays centred. Its important that the treadmill belt alignment is correct before going to the next step.

Step 5

Once you have the belt centred properly you can adjust the tension . Adjust both bolts evenly 1/4 of a turn at a time. Between each time walk on the treadmill at 4 km/h and try to stop the treadmill belt. It should slip for a moment and then grab. Keep repeating this step until the belt is tension properly. If tightening these bolts doesn’t stop the belt slipping your motor belt maybe the cause. If you try to stop the belt and it makes a grinding noise, it could be your roller pulley.

Step 6

Once you think you have the treadmill running belt tensioned properly carefully increase speed until you’re running. If it doesn’t slip then you’ve successfully tightened your treadmill running belt. If it does slip then your treadmill running belt wasn’t the problem .

I hope this helps and if your still having problems just give us a call on +64-9-836-0910 or e-mail me on [email protected] Regards Robert

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