Why Do My Mountain Bike Spokes Keep Breaking?

You love going on windy (and sometimes rough!) adventures with your faithful mountain bike.

You never used to have to think twice about its spokes, and barely even had them trued, but lately, they’ve been snapping like uncooked spaghetti.

You’ve replaced them again and again, but they continue to break after a few rides.

Is it your fault? Is your bike giving out?

Why do your mountain bike spokes keep breaking?

Keep reading to find out!

1. Spokes’ Tension is Too High or Unbalanced

Your spoke’s tension may be too high, causing the spokes to snap whenever your wheels hit something or ride on uneven terrain.

This is because the wheel could be too tight around the spokes, not giving them any space to bend or shift, causing them to break.

Your spoke’s tension could also be unbalanced with some spokes being tighter than others. This causes the spokes to move more whenever you’re cycling, which will wear them down quicker.

If you find that your bike’s rim is bent or twisted, there’s a good chance the spokes are unbalanced. So, you may need to fix or replace the rim before truing the spokes.

While many mountain bike spokes should be trued to 120 kilogram-force (or kgf), every bike model is different with some requiring a tension of 150 kgf.

If you’re an inexperienced mountain biker, we recommend taking your bike to a bike shop to be professionally trued.

However, if you’re up to the challenge of truing your bike yourself, it can be done at home with a few simple tools. You must use spoke keys to properly true your bike.

Avoid using other tools like a wrench, as this will only further damage your spokes and force you to replace them.

To learn how to true your bike’s wheels yourself, watch the video below.

2. Frequent Cycling on Uneven Terrain

Although mountain bikes are made to glide over the rockiest terrain, the spokes can still be affected by uneven ground.

While these effects can be mitigated by appropriately truing your wheels and inflating your tires to the correct PSI, the impact of continuously riding over sticks and pebbles will begin to show.

The bike’s wheels can be quite delicate, and become misshapen over time.

This will affect the spoke’s tension, causing them to break.

Even though you could never ask a mountain biker to resist riding through the roughest terrain they can find, we recommend frequently examining your rims to ensure they’re in good condition.

3. Intense Cycling

You’ve seen those photos of mountain bikers riding off a ledge and flying through the sky, before landing and cycling away, seemingly unharmed.

If you’re an experienced cyclist, you could perform these stunts without so much as a bruise to show for it, but your bike may not be so lucky.

Slamming down on your wheels after descending from a ledge or a curb, could damage the spokes and rims.

So, whenever you’re about to fly off a boulder for a picture-worthy moment, consider your spokes and prepare for a few of them to be broken or bent afterward.

4. Poor Design and Manufacturing

Did you get your wheels from a budget biking brand? Have they already started to break after a few low-impact rides?

If so, you may have purchased a poorly designed and manufactured wheel. These fragile wheels are usually built by machines and may be incorrectly tensioned.

The materials used to make them could also be of poorer quality, and more prone to wear and tear. Manipulating the metal by truing it could cause it to wear down in one place, resulting in it breaking the next time you ride your bike.

If you need to completely replace your wheel, we suggest ensuring it’s handmade by a reputable brand. You may even want to bring your new wheels to a bike shop to ensure they’re properly tensioned before taking them out for a spin.

5. Excess Weight

Have you gained a couple of pounds or gotten in the habit of carrying a heavy backpack with you?

This extra weight could be putting more pressure on your spokes, especially when you go on intense rides through rocky terrain.

Every time you ride off a curb or over a ditch, the excess weight is making it more difficult for your spokes to steady and support the wheel.

You may want to exchange some of your bike parts for lighter versions, ensure you’re wearing a light MTB helmet made of expanded polystyrene foam, and consider carrying fewer things in your backpack or finding more portable alternatives.

If your body weight is on the heavy side (e.g. a couple of hundred pounds), you may want to consider losing some weight or finding wheels that are strong enough to support your frame.

6. Deterioration After Years of Use

Even the best-quality wheels weren’t made to last forever. Your bike’s wheels have been your faithful companions for a couple of years, but it’s time to replace them.

While you can replace individual spokes for a reasonable fee, it’s best to replace the whole wheel if the spokes are snapping frequently.

The rim could be bent, or there could be another problem with the hub or spoke nipples.

So, to avoid replacing each spoke one by one before caving and buying a new wheel, head over to your local bike shop and have them advise you on the best wheel for your MTB.

Spokes may deteriorate over a couple of months or years depending on how intensely you cycle and where you ride your bike.

So, we recommend regularly checking your rims and spokes, and replacing them when you notice any signs of deterioration.