Trek Marlin Gen 3 Frameset

Marlin Frameset is a lightweight aluminum frame ready to be built into the perfect easygoing trail bike. It's loaded with all-new geometry that's more capable than ever, ideal for gaining confidence and speed on the singletrack.

• Marlin Gen 3 gives you serious trail capability with bigger tire clearance, internal dropper post routing, ThruSkew rear axle, and longer, slacker geometry that gives you more stability on steeper trails and at higher speeds
• You'll get a lightweight aluminum frame that's robust enough for the ride without weighing you down
• Fender mounts make it easy to accessorize, so your mountain bike can double as a rugged commuter
• Marlin models in XXS and XS frame sizes have a curved top tube and a lower standover height that makes it easier for smaller riders to mount and dismount
• Internal routing looks sleek and makes adding a dropper post easy

Expanded size range

With 8 different sizes, Marlin has a bike made to fit every rider. Each frame is equipped with smart wheel sizing, with XXS frames rolling on 26" wheels, and wheel sizes increasing proportionally along with frame sizes, so every rider gets the fit they need.

Trail-ready, Upgrade-ready

The secret to Marlin's popularity is a real trail-savvy mountain bike frame that's upgrade compatible, so it can grow with you as you take on bigger trails and tougher features.

Roll stronger with Thru Skew

Goodbye open dropouts. The Thru Skewer is a better, stronger, more precisely aligned rear wheel retention system that keeps your wheel more secure than quick-release skewers while still using the standard 135mm rear hub spacing.

A better way to produce aluminum

Starting in 2024, we began removing high-emission aluminum from our manufacturing and replacing it with low-emission aluminum made with renewable energy. By October 2025, nearly every alloy bike we make - this one included - had made the switch, driving a major drop in our footprint.

Frame	Alpha Silver Aluminum, curved top tube, internal derailleur & dropper post routing, rack and kickstand mount, 135x5mm ThruSkew
Skewer Rear	173x5mm QR
Seat Collar	Bolt-on, 36.4mm
Headset	Semi-integrated, 1-1/8''

Geometry Chart

B B Drop	3.8
B B Height	30.2
Chainstay Length	43.3
Eff Seat Tube Angle	74.0°
Eff Top Tube	52.1
Frame Reach	36.5
Frame Size Letter	XXS
Frame Size Number	13.5"
Frame Stack	54.4
Head Angle	66.5°
Head Tube Length	9
Offset	4
Seat Tube	32
Seat Tube Angle	74.0°
Standover	65
Trail	10.4
Wheelbase	106
Wheel Size	26"

Color

MATTE DNISTER BLACK