Trek Marlin 4, 5, 6, 7, and 8 Compared: Which One to Choose?

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In this article, I’ll help you navigate the Trek Marlin mountain bike family by comparing the Marlin 4, 5, 6, 7, and 8. 

You’ll learn about the differences between each model, who they are best suited for, and more. 

Plus, I’ll tell you which model gives you the best value for your money to help make your decision easier.

Trek Marlin 4 vs. 5 vs. 6 vs. 7 vs. 8

The following table summarizes the main differences between all Marlins that belong among the Trek hardtail mountain bikes.

Marlin Pros & Cons Summary

I summarized the pros & cons of the Marlin series below.

Marlin Main Features

Let me now explain the most important features of the Trek Marlin bikes.

Frame and Geometry

All Marlin bikes have the same aluminum cross-country frame, available in many sizes and colors that vary between models.

The XXS-S sizes have a differently shaped top tube, which is curved to increase the clearance between the rider’s crotch and the frame. This allows riders with shorter legs to stand over the bike more comfortably, for example, when stopping.

The frames of Gen 2 Marlins have a standard cross-country geometry, which provides a comfortable riding position and easy pedaling uphill and downhill. It also gives you easy maneuverability and visibility.

On the other hand, it’s not quite suitable for steep descents and challenging terrain – especially without a dropper seatpost.

The Gen 3 Marlins have a trail geometry (wider wheelbase), which provides more stability, especially when riding downhill. It’s similar to the Trek Roscoe geometry.

Lastly, it’s worth noting that the bike’s partially internally routed cables improve its overall appearance.

Suspension

One of the biggest limitations of Marlin bikes is their front fork suspension. These bikes are not primarily designed for challenging terrain but rather for those who want a versatile bike that can handle various surfaces.

All Marlin bikes have suspension travel of only 100mm, which is capable of absorbing small bumps. However, it’s not ideal for riding on rocky trails, and especially not for downhill riding.

Therefore, if you want a bike for more challenging terrain, choose one with longer travel (for example, the Trek Roscoe series).

All forks of Marlin bikes have suspension lockout. Lock it when riding on smooth surfaces for less energy loss when pedaling.

Wheels and Tires

The wheel size varies depending on the frame size. Frames smaller than size S are equipped with 27.5″ wheels, which are more agile and accelerate faster than 29″ wheels. Frames size M and larger have 29-inch wheels, which are more stable and better at maintaining speed.

All models have the same rims (Bontrager Connection, double-wall) except for the highest model, the Marlin 8, which has Bontrager Kove rims. The former rims are not tubeless-ready, while the latter are.

The same goes for the tires. The highest model already has tubeless Maxxis Ardent tires, while lower models have Bontrager XR2 Comp inner tube tires.

Groupset

The groupset is one of the main areas where the different models vary, and it’s probably the deciding factor for many people.

They differ primarily in the number of gears. Modern mountain bikes mainly use 1X drivetrains, which are popular due to their simplicity for maintenance and shifting. They are also lighter than 2X or 3X groupsets.

On the other hand, they offer fewer gears, so you may not always find the ideal one for your preferred cadence.

I recommend choosing from the 1X drivetrains, which are available on Marlin 6 and higher models. This way, you won’t have to think too much about shifting and cross-chaining.

Brakes

Another difference between the Marlin models is their brakes. The entry-level Marlin 4 uses mechanical disc brakes, while higher-end models have Tektro or Shimano hydraulic brakes.

Better brakes provide higher braking power. However, if you mainly ride on flat terrain leisurely, you don’t have to worry about a lack of braking performance.

Quality brakes are especially important if you plan on riding technical descents, so consider your riding style.

To learn more about disc brakes, read my article comparing mechanical and disc brakes.

Extras

Marlin frames have mounts for kickstands and racks, so you can easily install these accessories.

You can also use a Blendr stem, which is a mechanism that allows you to easily attach things like lights, speedometers, or bike computers.

The last detail is the lock-on grips that are easier to install and replace than slip-on grips.

Trek Marlin FAQ

My Verdict

So, which bike from the Marlin family is the best?

In my opinion, the Marlin 6 is the best choice because it has a modern 10-speed 1X Shimano Deore drivetrain and Tektro hydraulic disc brakes. Plus, it’s priced in the middle of the entire Marlin range.

Another option to consider is the Marlin 5, which is similar but has a Shimano Altus 2×8spd drivetrain, is lighter, and more affordable.

On the other hand, I recommend avoiding the Marlin 4 because it uses the outdated 3X drivetrain. The value of the Marlin 8 is also questionable, as you can get mountain bikes with better components in this price range.