Mountain bike tires have all kinds of knob shapes in different sizes. Each knob shape and size gives you a certain kind of ride experience. Understanding how tire tread patterns work and the various types of knob shapes available can help you match the right tread design to your riding style.
Also Read: Best MTBs for Entry-level Riders
In this short guide, I’ll describe 5 types of MTB tire knob shapes, 3 kinds of tread zones, spacing, siping, cuts, grooving, and more.
Types of MTB Tire Knobs and Sizes
The knobs of a mountain bike tire seat on a kind of base layer known as the casing. The casing itself is made of synthetic fibers, typically nylon. MTB tire makers layer these fibers in alternating directions.
To boost a tire’s puncture protection ability and stiffness, manufacturers sometimes add extra materials and layers before adding the tread. Below are five kinds of MTB tire knobs you need to know before choosing your next replacement bike tire.
5 Types of MTB Tire Knob Shapes
- Square-shaped knobs
- Ramped knobs
- Tapered knobs
- Micro knobs
- Darts and chevrons
Let’s now look at each of these knob shapes and sizes.
1. Square-shaped MTB Tire Knobs: Offer Great Traction
Good for:
- Rolling over moderately rocky terrain
- Biking over gravel
- Riding on dirt trails
These knobs are more or less square in shape/design. Or at least, they’re noticeably less round. Compared to knobs with a rounder shape, square knobs win out in the traction department.
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They dig deeper into the surface and give your ride a solid, stable feel. But tire treads that offer greater grip almost always have more roll resistance. And more rolling resistance equals less speed.
Square-shaped knobs are good for riding over dirt trails and gravel. You can also reliably use them for rolling over moderately rocky terrain.
2. Tapered MTB Tire Tread Pattern: Best for Wet, Muddy Conditions
Tapered knobs are larger at the bottom and get small toward the upper end. That is, they taper the farther away you get from the base of the tire knob.
Tapering MTB tires makes it harder for mud and dirt to clog up the tread. Tires with this kind of tread pattern sort of self-clean as they roll on the ground. This is the kind of tread pattern you need for biking over soft, wet, muddy surfaces.
Tires with this knob design typically have a low knob count, and there are enough spaces between them. This tread pattern clears mud really nicely. And when you’re rolling over firm terrain, they dig right in and provide a decent level of grip.
Tapered MTB tire treads are best for:
- Soft terrain
- Muddy conditions
- Wet surfaces
3. Ramped MTB Tire Tread Design: Great Braking And Rolling Efficiency
Ramped tires are designed to have reduced roll friction and great braking power.
To ramp a tire, manufacturers make one of the knob’s front angle somewhat slacker while making the back of the knob stand at a steeper angle. The rear of the knob looks almost vertical relative to the casing.
With this tread design, you’re going to have really nice rolling efficiency. And the moment you pull the brake levers, the knobs quickly bite into the riding surface, keeping you secure and safe out on the trails.
This tread pattern lives on the cusp of relatively mild acceleration forces and massive braking forces.
Good for:
- Braking and safety when out biking
- Fast rides on demanding terrain
4. Micro MTB Tire Knobs: for Gravel, XC, and Cyclocross
Micro MTB knobs are pretty small compared to all the other tread types discussed in this bike tire knob guide. Also, these knobs stand short and are pretty compact.
The overall design makes for a relatively lighter tire, something many cyclists want. Because lower tire weight translates to enhanced rolling efficiency. Also, smaller/shorter knobs tend to experience more uniform flex in relation to the casing.
However, some MTB tires with this knob design these days tend to deform when you’re cruising down the trail at a high speed. When they deform, roll resistance increases. And you got to pedal that much harder for the same amount of forward propulsion.
If you mostly bike on gravel roads or paths or are a cyclocross or cross-country mountain biker, get tires with this kind of knob shape/design.
One disadvantage of micro MTB knobs is that they provide less grip when you’re traversing along loose trails.
Good for:
- Racing: Xyclocross and cross-country mountain biking
- Riders who prefer lightweight MTB tires
5. Darts and Chevrons: Improved Front-wheel Turning Efficiency
Darts and chevrons are cycle-speak for angular or pointy MTB knobs designed to offer relatively large, horizontal, forward edges. While the forward edge of the knob is pointy or angled, the rear edge is designed to give you a better braking ability.
But better braking isn’t the only thing you get from darts and chevrons. The horizontal edges make for increased turning efficiency. Since turning efficiency is where this tread design shines best, tires with these knobs are often used on the front wheel.
Does Knob Spacing Pattern Matter?
Wider spacing between the knobs = better grip and less mud and loose dirt caking into the tread. Good for downhill MTB tires
Narrower/Less spacing = Less rolling resistance. GFood for cross-country tires
Yes, spacing matters, as does tread design. The shape and angling of these rubber knobs and the amount of space between them make a difference.
A tighter tread design with little spacing between the knobs translates into a smoother forward roll thanks to the reduced roll resistance. That’s the kind of tread design spacing you want on a cross-country wheelset.
Having large knobs with wider spacing enables the tire to dig deeper into the surface, increasing grip. This is the kind of tread design and spacing you see on the classic downhill MTB tire.
Wider spacing also makes sure that the tire spits mud and loose dirt out so they won’t lodge between the knobs and harden up.
3 Types of Bike Tread Zones
Bike tire makers don’t position knobs uniformly throughout the surface of the tire. Also, knobs aren’t always the same size even on the same wheel. Manufacturers organize MTB tire tread patterns around three zones namely:
- Center tread zone
- Transition tread zone
- Side tread zone
Let’s learn more about each tread zone.
Center Tread Zone: Useful for Mostly Straight Trails
The center tread zone is pretty much the workhorse on any kind of MTB tire. It’s the largest of all three tread zones. Virtually the entire zone stays in contact with the riding surface and that’s where the majority of rider weight goes.
Since you’re rolling on the center zone nearly all of the time, it vastly determines the total amount of rolling friction a tire faces. Whenever you’re riding on a more or less straight trail with minimal cornering, it’s the zone you’re counting on.
Also, this zone influences the wheel’s straight-line grip and the overall braking power you can expect from a wheel.
Some manufacturers opt to put smaller knobs spaced closely on the center zone to lower rolling drag. But they can’t do that without adversely affecting grip and braking ability. This bike tire knob placement works best when riding over mostly hard-packed trails and surfaces.
What if all you have is loose dirt trails? Get a wheelset with a center zone that has larger knobs and wider spacing.
Transition Tread Zone: for Moderately Deep Turns
Sitting on either side of the center zone are the transition zones. If you need to lean a tad some of the time on a singletrack with moderate turns, you’re going to need to rely on the transition zone.
If a tire manufacturer wants their tire set to provide more grip in the transition zone, they usually increase the number of knobs there. But remember the more knobs in the transition zone or anywhere else, the more roll friction.
Side Tread Zone: for Really Tight Corners
When you’re riding on trails with many twisty turns and berms, you’re going to need to use deeper lean angles. And that’s where the knobs on the side zone come into play.
Typically, side tread zone knobs are larger than those on either the central or transition zones. The knobs are larger here so that you can have as much traction as you need when negotiating really tight corners.
You’ll always use the side tread zone knobs of your tires less often than those on the other two zones. And because side zone knobs are shaped to increase traction, there’s a bigger loss of roll efficiency there.
The good thing is that you use this zone momentarily rather than constantly. Therefore, roll efficiency loss isn’t a major concern.
How Long Do Bike Tires Last?
Bike tires generally last anywhere between 1,000 miles and 3,000 miles. You should be able to squeeze at least 2,500 miles out of most top-end tires and of course less mileage from cheaper options. In the end, bike tire durability depends on the nature of the trails you mostly ride on and your biking frequency. For example, if the trails you ride have dozens of really tough rock gardens, your tires won’t last long.
Siping, Cuts, Grooves, and Studs
Bike tire designers have other ways aside from treads to make tires behave in certain ways during use. Siping, cuts, grooves, and studs are all different approaches to giving tires a nuanced roll quality.
Siping/Sipes in MTB Tires
What’s siping on MTB bike tires? Siping or sipes refers to small sawtoothed cuts made into tire lugs usually to increase traction on wet, slippery roads. Siped tires would be a worthy buy for you if you do tons of road tours and rides on wet, smooth asphalt. Siping gives tires rugged, elongated edges. And these edges increase multi-directional grip.
These sawtoothed edges open up when the tire flexes. When this happens, the water between the wheel and the ground gets ejected. What’s more, siping may compel the knobs to deform in desirable ways, empowering the wheel to ride better when cornering gets harder.
It’s possible to sipe your MTB tires if you need to do that. However, those who do it often report marginal improvements as far as overall traction.
MTB Tire Grooves
These look similar to wider sipes without the tiny zigzag edges. Some people use the terms grooving and siping interchangeably, but there’s a difference.
Grooving gives tire lugs extra edges, which translates to greater traction. A tire with cuts and grooves usually demonstrates better turning and braking capabilities. Also, you’ll notice less struggle when it comes to acceleration.
MTB Tire Studs
Do you see the tiny holes in the tire lugs above? Metal studs can be sunk into these holes to increase a wheel’s ability to roll over icy, snowy surfaces. Many fat bikes have studded tire lugs for this very reason.
MTB Tire Compound Matters, Too
Designers formulate all kinds of tire compounds, and each formula works a little differently than the others. These creative folks pair up each lug design with a specific compound to create a tire that performs in a certain way.
A good rubber compound provides the kind of tire flex required so that the lugs can perform as desired. So, you should pay attention to all these considerations when shopping.
What’s a Pinch Flat?
A pinch flat happens when a mountain bike wheel hits a rock or root with a massive force, rupturing the inner tube. The compression from the hit object as well as the rim focuses on the rubber tube, pinching it.
The result is a pinch flat, also called a snakebite in mountain biking lingo. That’s because it looks like two tiny holes not different than those made by a snake when it sinks its fangs into something…hopefully not your leg. Here’s how to ride your mountain safely in places with rattlesnakes.
This type of flat is the main reason many off-road riders today favor tubeless setups over the classic inflated-tube-inside-a-tire setup. In a tubeless setup, there’s no tube inside the tire. Instead, the tire bead locks into a special rim and a substance called a sealant self-mends any tiny holes from the inside out.
What’s a Puncture Flat?
A puncture flat is what happens when a sharp object such as a nail or a thorn pricks through the tire and pierces the tube inside. It’s a common issue with tubed MTB tires. While tubeless tires may not eliminate flats entirely, they can minimize them significantly.
Wrapping It Up
There are at least 5 different kinds of tread MTB knob shapes and designs. Each design demonstrates super performance in specific trail conditions. Make sure to choose a tread pattern that will match the nature or quality of your trails.
The amount of spacing between the tire lugs also matters as does the tire compound and other special treatments such as sipes, grooves, cuts, and studs.
Happy mountain biking!