Trek X Caliber 6 Review | PedalChef

Key Takeaways

  • If you’re shopping for a used hardtail bike, the X-Caliber 6 is an inexpensive option that performs well.
  • Newer bikes will get you more advanced components at the same MSRP if you want to upgrade.
  • Component highlights include the Sram X4 drivetrain and Shimano hydraulic disc brakes.

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If you’re looking for an entry-level hardtail, it can be hard to sort through the options. This review will help you decide if the Trek X-Caliber 6 is for you.

The Trek X-Caliber 6 is a solid bike overall for anyone just getting into mountain biking. Trek continued this bike after 2016, but you should be able to find it used for a good deal. If you want the modern replacement, the Trek Marlin 6 has similar performance with updated components and design.

I am a dedicated hardtail rider, and I love finding bikes that let you ride hard without needing complex rear suspension. For this review I dug into the details on the Trek X-Caliber 6 and compared it to similar bikes to give you everything you need to know before making a purchase.



Trek X-Caliber 6 Performance

Coming in at $750 MSRP, the Trek X-Caliber 6 is definitely an entry-level mountain bike, so you shouldn’t expect mind-blowing performance. For what it is, the Trek X-Caliber 6 does a good job. With cross-country-oriented geometry and budget (though highly functional) components, it’s ready for fun laps on flowy trails.

It does offer a confident, stable ride that provides real off-road fun on moderate trails. Would I tackle aggressive Moab terrain on this bike? Probably not. But for laid-back riding around local singletrack trail centers, this is a competent choice.


With relatively old school cross-country-inspired geometry, this mountain bike isn’t designed for shredding downhill. If things get steep and rough, this bike will feel out of its element pretty quickly.

Rather than taking this on the roughest terrain you can find, you need to chase out smooth, flowy singletrack where you can feel in complete control and really have fun. The front suspension will get overwhelmed by big hits, but on smoother trails it does a great job of muting out buzz and keeping you comfortable.


While this bike is passable for descending, the race geometry and nimble aluminum frame really shine on the uphills. It isn’t super light, which is to be expected for the price, but still is quite lightweight for an entry-level bike. When you hit steep climbs, you’ll find yourself impressed at how eagerly this bike pedals up and over obstacles.

The aluminum frame is lightweight, stiff, and does a great job at getting your power down to the ground. If you’re coming from a heavier, older mountain bike, you’ll definitely

Trek X-Caliber 6 Frame and Geometry

The Trek X-Caliber 6 is built around a nimble aluminum frame with mechanically formed butted tubing. This frame is plenty stiff and strong for most trail riding, and the light weight will help you out on the uphills.

For an inexpensive entry-level bike, this frame has a surprising amount of modern features. Internal front derailleur routing keeps it looking clean and streamlined. Race geometry makes it feel quick and maneuverable. It even has size-specific wheel clearance, with 27.5-inch wheels for XS and S, and 29-inch wheels for size M and above.

Specs and Components

With budget mountain bikes, it’s always a balancing act for manufacturers to spec components that perform well enough while still hitting a price point. Overall, I think Trek did a good job with the X-Caliber 6.

Here are some of the component highlights to give you an idea of the build spec.


The X-Caliber 6 comes equipped with a Sram X4 with an 11-34 cassette in the back and 44/32/22 chainrings.

This is definitely not the most advanced or modern drivetrain available, but it’s pretty on-par with what you should expect from an entry-level bike from 2015. If you are looking for an up-to-date bike, there are 1x drivetrains available in the same MSRP price range, but for an older bike, this is a decent drivetrain.

One benefit of the 3x9 setup is that you get more gear range than comparable 1x drivetrains. The low-end climbing gears aren’t as low as I’d like, but the 44-tooth high end chainring gives you great high gears for speed. This is especially nice if you’ll use this bike for pavement riding and commuting.


This bike is a hardtail, so you have no rear suspension here. For the type of riding this bike is designed for, that can actually be considered an advantage. Hardtails are naturally more efficient and better at putting your power down for climbing and pedaling.

On the front end you get a 100 mm travel Suntour SR XCM fork. This is definitely a budget fork, but it offers decent performance for most riding. As a coil spring fork, it will be significantly heavier than air-sprung forks, but that’s what you can expect from a bike at this price.

Overall, I think you’ll be pleased with the performance of this fork. It is relatively smooth, and the travel helps even out rough sections of trails.


Brakes are a common place for manufacturers to cut corners on budget bikes. It’s nice to see that the X-Caliber 6 comes with Shimano hydraulic disc brakes. If you are coming from mechanical brakes, you’ll be impressed by the awesome stopping power from these Shimano M355 brakes.

Many similar bikes come with cheaper mechanical disc brakes, so this is definitely a highlight of this build.

Wheels and Tires

The wheels on this bike are pretty standard Bontrager alloy rims and hubs. On size XS and S, you get 27.5-inch wheels, while size M and above come with 29-inch hoops.

These wheels come fitted with Bontrager XR1 tires. These are fast-rolling tires designed to emphasize efficiency and light weight over maximum grip. They still have decent side knobs for superior corner traction.

I wouldn’t count on these tires for ultimate grip in loose conditions, but they do a good enough job for most packed singletrack riding.

Competition for the Trek X-Caliber 6

The X-Caliber 6 fits into a crowded budget-mountain bike market. There are a lot of other options to choose from, so it’s important to know how it measures up to the competition.

The most important thing to note is that the Trek X-Caliber 6 was discontinued in 2015, replaced by the Marlin 6, so you won’t be able to find an X-Caliber for sale again. This will make a difference with the bikes we’re comparing it with, because they are newer and currently available for sale.

Trek X-Caliber 6 vs Trek Marlin 6

Trek Marlin 6
Trek Marlin 6

If you’re wanting to get a bike that’s similar to the X-Caliber 6 but in a more modern, updated package, the Trek Marlin 6 is the bike that replaced the X-Caliber 6 in Trek’s lineup.

These bikes share a lot of the same DNA with lightweight aluminum frames and cross country race-inspired geometry. They have similar spec’d forks, and brakes as well.

The biggest difference will appear in the drivetrain. While the X-Caliber 6 used an old-school 3x9 drivetrain, the Marlin 6 has a more modern setup with a Shimano Deore 1x10 speed drivetrain.

It really will come down to personal preference, but 1x10 drivetrains are the new industry standard for mountain bikes. If you are okay with older technology and design, you can probably find an X-Caliber used for a much lower price.

Trek X-Caliber 6 vs Giant Talon 2

Giant Talon 2
Giant Talon 2

Giant is one of the most popular brands in the mountain biking world, and for good reason. Their business model enables them to offer seriously capable bikes at much lower prices than competitors.

The Giant Talon 2 competes directly with the X-Caliber 6 (or Marlin 6, nowadays) in the entry-level hardtail market, and there are a lot of similarities in geometry and components.

Again, the biggest difference is going to be the drivetrain. The Giant Talon 2 uses a Microshift Advent 1x9 setup compared to the X-Caliber’s 3x10. While this drivetrain doesn’t get as much publicity as products from Sram or Shimano, I’ve been very impressed with the Microshift Advent lineup.

This drivetrain is designed to be affordable, reliable, and durable. It offers the same gear range as Shimano’s 10-speed Deore, but with a thicker 9-speed chain and simplified adjustments.

With more aggressive geometry and sensible component selection, I think the Giant Talon 2 is definitely worth looking at if you are in the market for an entry-level bike.

Trek X-Caliber 6 vs Cannondale Trail 7

Cannondale Trail 7
Cannondale Trail 7

The Cannondale Trail 7 is another popular bike that slots into a similar price bracket. As with most bikes in this market range, there are a lot of things that are similar, with just the small details making the difference.

This bike has basic hydraulic disc brakes, as coil-spring fork, and internal cable routing like the others compared here.

The Cannondale Trail 7 is a little behind the times with 2x8 shifting. Even the older X-Caliber gives you more range and better gear spacing with its 3x9 setup.

Overall, if you are looking for a budget hardtail bike, I think you’ll be better off with the Trek X-Caliber 6 than the Cannondale Trail 7.

Where to Buy the Trek X-Caliber 6

Unfortunately the Trek X-Caliber 6 is out of production and is no longer available to buy new. That said, it’s definitely worth looking around for a used one. Bicycle Blue Book estimates the value of a 2016 X-Caliber 6 at under $250, so you can get a great bike for not much money.

If you are looking to buy the modern successor of the X-Caliber 6, here are places you can find the Trek Marlin 6 for sale: