Your mountain bike gets you from A to B through rough terrain, over grassy gaps, and through dangerous dirt roads, but when you break down the science behind it, you’ll find the the bike’s weight has a great deal to do with that success.
Your mountain bike weight attributes to speed, drag, turning, and so much more.
We’ll go over the average bike weights, what you have to consider if you modify the bike, and all the little juicy bits in between that help you understand your mountain bike even better.
- 1 How Much Should a Mountain Bike Weigh?
- 2 What Happens if a Mountain Bike is Too Heavy?
- 3 Can a Mountain Bike be Too Light?
- 4 How Heavy Should a Mountain Bike be for a Roof Rack?
- 5 Do Modifications Seriously Alter Bike Weight?
- 6 Finding a Healthy Balance
How Much Should a Mountain Bike Weigh?
The average weight of your common mountain bike is about twenty-eight pounds.
This is with an aluminum frame, high quality suspension fork, lofty saddle, and two thick-and-bulky mountain bike tires.
Modifications can either maintain, increase, or decrease the weight of a mountain bike.
That’s a good weight. You can have enough traction on the road from the force of the bike, but you aren’t going to stress out your legs pulling a ton of weight with all that pedal power.
Somewhere around this weight is a good goal to shoot for.
Why is this weight so important? Well, if it’s too heavy, you run into problems.
If it’s too light, you run into problems. You have to be like Goldilocks and find the “just right” weight, while also keeping your input in mind.
What Happens if a Mountain Bike is Too Heavy?
You’re just dragging the weight against the ground, really.
If your mountain bike is too heavy, you’re stressing your body out just to pull it.
That sounds like a good way to use resistance training, but it’s not—that’s why we have resistance levels on multi-speed bikes.
This is what can happen if your mountain bike is too heavy.
Muscle Fatigue Becomes an Issue
We can manually increase the resistance on our mountain bikes by choosing different speeds, but that’s a choice we get to make.
On the days where we don’t feel like pushing beyond the limits, we can leave it a little looser.
If the bike is heavier, you’re just stuck with that. Then you work on higher intensities on the multi-speed dial, and you wonder why you’re having difficulty on the lower end of the spectrum.
Increased drag simply means that you turn less fluidly because you’re pushing extra weight, you’re moving slower than you should be, and the bike feels taxing on your muscles rather than beneficial.
It should feel like a workout; not a burden.
Using it for Commuting Becomes a Pain
Mountain bikers still have a nine-to-five to work, right? If you live in the city or your commute is too short to mentally justify driving a car, you can take your mountain bike into work.
If it’s too heavy, lifting it up a staircase into the building or to bring it on the elevator becomes a struggle, and nobody wants to be seen struggling with something like that in public, either.
After hopping off the bike and being a little fatigued, lifting a heavy bike is a chore.
It also means that at the end of your workday it’s going to feel like you’re pulling twice the bike’s weight when you add eight or more hours worth of work to the fatigue feeling.
To the same effect of having more drag, your speeds will be significantly slower.
The human body can only produce so much pedal power, so unless you mountain bike 60+ hours per week and have legs of steel, you will notice the difference in weight and be impaired by higher weights.
That being said, when you look at the important notes about your bike being too light, you still want enough weight here that you have sufficient traction.
You don’t want your bike to be so light that your speed is off the charts, but you also shouldn’t make yourself work harder when you don’t have to.
It isn’t all bad. You do get much better traction with a heavy bike, but that means little when you’re not even going at a sufficient enough speed to pose a risk for loss of control.
Having a heavy bike and going downhill means better control though, so that’s a bonus.
Heavier bikes have their balancing perks, but nobody wants to lug it in and out of the house.If a heavier bike fits your style, look for bikes in the 30-34 pound range to get a good mix of power and balance.
Can a Mountain Bike be Too Light?
It sure can be. Without enough weight to the frame, you might feel like you’re not pedaling as much and yet you’re absolutely flying down the trail.
That feels good in the moment, but it has some core issues that we should discuss. Keep in mind that this is relative to the bike’s exact weight, and the rider weight.
These are some problems that you’ll encounter if your bike is too light.
Going Too Fast
More speed does not always equal a better experience.
If the bike is too lightweight, your pedal power is going to make the bike move really fast, and then cause an issue with our second pain point.
Loss of Control
If the bike moves too fast, it begins to wobble because there isn’t enough equalizing weight in the middle of it. This doesn’t happen with heavier bikes.
While some of this comes down to user control and self-balancing, you can’t deny that the weight of the bike can make it easier or harder to balance.
Low-Quality Frame and Parts
This is subjective. But making things lightweight and trimming off fractions of ounces is an obsession. We see it with phone models every year, monitors, lighter TVs, the list goes on and on.
A lighter bike can be good, but it either means that the material that was used is more lightweight based on its construction (unique alloys), or that it’s thin because they skimped on material volume, and it’s actually not that durable.
A cheap, lightweight bike isn’t a good sign. There’s a reason that even budget-friendly mountain bikes have aluminum frames: it’s cheap and heavy, so it might weigh a few more pounds than the competitor’s mountain bike, but it’s not that big of a deal.
Easier Time Moving Indoors/Outdoors
It’s not just a list of negatives. It’s going to be much easier to bring this indoors and pull it back out, even if there are stairs to contest with.
A lighter bike means that even if the size of your 29” bicycle is a bit wonky, a lower weight gives you better control when manually moving this.
It’s also better for overstretched bike racks if you don’t have a high weight limit on them.
You’re riding on a trail, your bike feels nice and light, and everything is just cruising along at an even pace.
Then you hit a hill, and even on a low resistance level, it feels like you’re climbing Mt. Olympus. Why is that?
It’s a mental game that lightweight bikes force us into, because those leisurely strolls will be so simple compared to trekking uphill. It isn’t actually harder, though, so that’s a bonus.
Lightweight bikes aren’t necessarily better, it all depends on your riding style.
If you’re going to spend most of your mountain biking time on level, even trails, it will make the trip easier. Just be sure to use those resistance levels so you get a workout in.
How Heavy Should a Mountain Bike be for a Roof Rack?
Thankfully, most manufacturers of roof racks for bicycles up to 50-60 pounds per bicycle, and you’ll find mountain bikes between 26 and 34 pounds most often, so roof racks and rear racks aren’t going to be an issue.
Just be sure that when you shop for one, you find the maximum weight capacity per bike and not just the total.
Do Modifications Seriously Alter Bike Weight?
It depends on what modifications you’re considering.
Many aluminum frame water bottle racks only weigh a couple of ounces, so it won’t drastically increase your drag or anything along those lines.
You just have to think about what the modifications mean, because the extra weight of 24 oz of water adds to your gross weight as well.
If you modify the back of the bike to include a milk crate, the modification itself, crate, and its contents will all influence the weight.
Keep this in mind by knowing the base weight of your bike, and documenting the weight of all the modifications you use.
Finding a Healthy Balance
You want a lightweight bike that helps with your dexterity and control, but not so light that it has no ability to hold its own weight under intense speeds.
Be wary of too many modifications, and don’t cheap out on a roof rack if you like to take your mountain bike to trails far away from home.