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Editors Note: This article is courtesy of the team at Art's Cyclery. The original post can be found here.

Tires are a critical ingredient in your bike's performance recipe, ranking just below suspension design and components in terms of impact. Factors like tread pattern, volume and compound all contribute to how your bike handles. Beyond these basic concerns, there's also the interaction between the front and rear tires to consider. Handling different duties, front and rear tires usually have different tread patterns and profiles, width, and even casings.

Front tires are where most of your control comes from. Since wider tires weigh more, but also provide increased traction and forgiveness, split the difference and put a higher-volume tire on your front wheel. A bigger contact patch makes for better steering control, and the higher volume helps to absorb big hits and maintain control in critical situations. Also, the extra weight doesn't have as much of a perceived effect as it would on the rear wheel, which is directly attached to your drive train and thus, your legs.

Testing the transition zone. Photo courtesy Art's Cyclery

Testing the transition zone is key to understanding how a tire performs (click to enlarge). Photo courtesy Art's Cyclery​

Rear tires are where the power from your muscles turns into forward momentum. For this reason you want to use a rear tire with enough tread for traction, but not enough to create excessive resistance. This is also why a narrow tire goes on the rear wheel; it's lighter, requiring less energy to rotate. Additionally, rear tire tread designs should complement the front tire, but can be very different to achieve rear-specific goals.

Read our review on the Michelin Wild Rock'R2 all mountain tire.


Tread profile is also important. Round tread profiles tend to be more forgiving and versatile. Square profiles excel in loose dirt and tend to "carve" (until the breaking point is reached) compared to a round profile's driftier feel. When mixing profiles, advanced riders should try a square front and round rear. Up front, once you have figured out how hard the square profile tire can be pushed, you'll have an accurate and locked-in tire guiding you around turns. Since the rear wheel follows a wider arc than the front, it's nature is to drift a bit more as it tries to follow the front tire around a turn, and a round profile will help maintain control during the drift.

Taller knobs dig into loose terrain, but are squirrely on hardpack. Wider knobs offer more stability. Lower knobs roll faster, but don't provide enough grip in loose terrain.

Taller knobs dig into loose terrain, but are squirrely on hardpack. Wider knobs offer more stability. Lower knobs roll faster, but don't provide enough grip in loose terrain (click to enlarge).​

Taller knobs dig into loose terrain, but are squirrely on hardpack. Wider knobs offer more stability. Lower knobs roll faster, but don't provide enough grip in loose terrain. Open transition zones between center and cornering tread zones (Continental Der Kaiser) offer more outright cornering grip and maintain straight line speed better, but are not as forgiving or predictable as tires utilizing transition zones with knobs (Hans Dampf).

Continue to page 2 for more tire talk plus recommendations on which combinations work best »

Trail/all-mountain tires show a combination of reduced weight for climbing and acceleration, along with traction and protection against pinch flats. Photo courtesy of Art's Cyclery

Trail/all-mountain tires show a combination of reduced weight for climbing and acceleration, along with traction and protection against pinch flats. Photo courtesy of Art's Cyclery​

Different disciplines place different requirements on tires, demanding specific features tailored to each use. Trail/all-mountain tires show a combination of reduced weight for climbing and acceleration, along with traction and protection against pinch flats. When choosing, err on the side of protection, width, and increased knob height/volume. Look for Reinforced sidewalls, but stop short of full DH casings. Schwalbe's Snake Skin casing is a good example.

Cross-Country tires must be lightweight and have low rolling resistance above all. Go with single-ply sidewalls if rocks and technical terrain are not issues. Very low profile knobs cut down weight and increase rolling speed.

When choosing downhill tires, flat protection and cornering speed are your main concerns. DH tires have beefy casings for pinch flat protection and structure to run low pressure. Large volume, aggressive knobs dig in and grab through turns and provide confident bike handling and effective braking.

Nothing will change the ride on your existing bike quite like a fresh set of rubber. The correct choice for you is going to depend on your local trail conditions, your riding style, and your skill level. It's okay to mix and match brands for front and rear tires to get the perfect combination. When asking for opinions on tires, keep in mind everyone's preferences on what factors are most important will be a little different. But with this primer on tire performance, you should be able to decode the complexities of all the tire options available and get the set that is going to work best for you. Use the chart below as a starting point when looking for an effective front/rear tire combination.


 

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"Ranking just below suspension design and components?"

Uh, no, tires are more important than either of those things. As literally the only part of your bike in contact with the ground, if there is one place to spend money, it's the tires.
 
I have used many of the tires on this list, and the Michelin Wild Race'R is not a trail / all-mountain tire. It is XC.

Also, the Ikon rolls much faster than a Crossmark and is better in every way, except price. Ikon 2.35 front and 2.2 rear is a good combo, or 2.35 on both ends.
 
Are you sure about this: "Also, the extra weight doesn't have as much of a perceived effect as it would on the rear wheel, which is directly attached to your drive train and thus, your legs."

I don't think it's true unless you are constantly in a wheelie/manual. When we move forward, we need to overcome the inertia of both wheels. Your chain connects your legs to the rear wheel, but the ground connects your rear wheel to your front wheel.
 
I'd swap the Conti Mountain King for the X-king on the back. The X-King rolls better, it still has good grip. My personal "best choice" is the Hans Dampf TSC on the front and the Conti X-King 2.4 protection on the rear.
 
Wuffles, I agree with you. However, I believe the premise of the article is "once you have purchased your bike (based on suspension design, how it rides, components, price, weight, etc...), what is the most important ingredient".

I think it could have been made a bit clearer in the opening paragraph.
 
TC, again, I think this point could be made just a bit more clearer. The issue is that IF rider weight distribution was 50/50 (front/rear), then the weight of the front would matter as much as the rear. For general riding conditions, the rear supports most of the riders weight so therefore the weight of the rear tire factors in more than the front tire.

You don't have to be in a constant manual/wheelie in order for the front to be carrying less of the riders weight (and overall bike/rider weight) at any given time (minus such things as pumping, pre-loading, etc...)
 
Gregg, weight distribution has absolutely no effect on how the front or rear wheels/tires change in angular momentum. Acceleration is a direct relationship with the amount of net force applied to the bike/rider. The tire's rolling resistance matters and the weight distribution of the rider affects the net force if one tire's rolling resistance is more than the other. But the statement TC was referring to is a common misconception that the weight of the rear tire somehow has more effect on acceleration than the front.....unless this idea of "perceived effect" is something in one's mind that one has to overcome because of a held belief.
 
"Since wider tires weigh more, but also provide increased traction and forgiveness, split the difference and put a higher-volume tire on your front wheel. This is also why a narrow tire goes on the rear wheel; it's lighter, requiring less energy to rotate."

This is presented as fact without any backing. It is also not correct.

Why do you NOT want a smaller volume rear tyre?

In general you choose tires front and rear to optimize the characteristics you want. That mostly means, as indicated in the article, that you choose a faster rolling rear (due to higher load) and a grippier front for handling. But this has very little to do with tyre volume.

First, rolling resistance. Faster rolling does not mean smaller volume. That is a well established fact (look up Peter Nilges' study on rolling resistance or the same topic on wikipedia). To reduce rolling resistance off road you need lower pressures and that means you need more volume to avoid pinch flats. There is no two ways about it unless you run Procore.

Second, grip. Less pressure = more grip. More volume let's you get away with a an even easier rolling rear tyre and still have the same level of grip.

Third, weight. A popular trail tyre like the Maxxis Ardent EXO/TR 29 weighs, hold on, only 5g more in 2.4" vs 2.25". Schwalbe Nobby Nic Pacestar Snakeskin in 2.35" on the other end is 75g heavier than a 2.25". Still, hardly a difference to be felt. The weight difference between big vs slightly smaller volume is getting smaller every year and the argument has pretty much lost it's value.

BTW, a heavier tyre does not require more energy to keep spinning, in fact, it keeps it's momentum better. A heavier tyre requires more energy to speed up and brake.

Are there other factors to consider? If you prefer the way your bike handles with a smaller rear tyre, that is of course a valid argument - for a very small percentage of riders who are at that level of finesse.

So what's the conclusion? You choose a tyre with as much volume as your riding conditions require and your frame allows, but there are no reasons to go for a smaller rear tyre for better performance. If anyone can convince me that I'm wrong, I'm all ears :)
 
Wuffles, we hear you, and will agree that tires are AS important as those things. However, a poorly designed suspension design or fork that doesn't work smoothly will keep your tires from doing their job properly. If your tires are skipping and bouncing off the ground then even the "best" tread/compound/casing in the world won't help much. But components? Yeah, OK, that could be a bit of a stretch.
 
"This is also why a narrow tire goes on the rear wheel; it's lighter, requiring less energy to rotate.
"simenf", I couldn't agree with you more. I'll always use the widest tire I can fit into my frame. If the above were true we wouldn't be seeing the trend towards +(plus) tyres.
There is also the technical posting on the schwalbe site: Why do wide tires roll better than narrower tires?

http://www.schwalbe.com/en/rollwiderstand.html
 
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