Trek Marlin 5 Gen 3 Mountain Bike 2025 - Hardtail MTB
The Marlin 5 Gen 3 pairs trail-ready features like a 100mm suspension fork and powerful disc brakes with commuter-friendly mounts and smooth Shimano CUES shifting—perfect for off-road starts or rugged rides to work.
Key Features:
- Alpha Silver Aluminium frame with internal cable routing and modern geometry
- SR Suntour XCT 30 coil fork with 100mm travel and hydraulic lockout
- Shimano CUES U4000 9-speed drivetrain with wide-range cassette
- Tektro 160mm hydraulic disc brakes for consistent stopping power
- 29” Bontrager wheels with XT3 Comp 2.4" trail tyres
- Rack, kickstand and mudguard mounts add daily versatilit
- Available with 0% APR finance
The Trek Marlin 5 Gen 3 is a brilliant entry point into mountain biking and doubles up as a tough, adaptable ride for everyday use. Built around a durable Alpha Silver Aluminium frame, it brings together thoughtful design and real off-road capability with a geometry inspired by Trek’s more advanced trail bikes. With room for wide 2.4” tyres and a stable, confidence-boosting feel, it’s ideal for tackling mellow trails or navigating town with a bit more grip and control.
Up front, the SR Suntour XCT 30 suspension fork with 100mm of coil-sprung travel takes the edge off bumpy trails, and the hydraulic lockout is great when switching to road sections or climbs. It’s paired with a Shimano CUES U4000 9-speed drivetrain, offering smooth shifting and a wide 11–46T cassette for all-round terrain coverage.
Braking duties are handled by Tektro hydraulic disc brakes with 160mm rotors perfect for reliable stopping whether you’re rolling through muddy tracks or dodging traffic. The bike rolls on 29” Bontrager Connection wheels wrapped in XT3 Comp 2.4” tyres, giving a good blend of traction and speed on mixed surfaces.
Practical features like internal cable routing make for a clean look and easier upgrades such as fitting a dropper post. You’ll also find mounts for racks, mudguards and a kickstand, giving the Marlin serious potential as a daily ride, campus commuter or multi-use explorer.
In smaller sizes (XXS and XS), the Marlin 5 features a curved top tube and lower standover height, making it easier for smaller riders to mount and dismount safely and comfortably.
Whether you’re heading into the woods, commuting across town, or just getting started with your mountain biking journey, the Trek Marlin 5 Gen 3 gives you a dependable, confidence-inspiring platform at excellent value.
Occasionally, without notice, manufacturers change product design and/or specifications.
| Frame | Alpha Silver Aluminium, internal derailleur and dropper post routing, rack and kickstand mount, 135x5 mm ThruSkew |
| Fork | SR Suntour XCT 30, coil spring, preload, hydraulic lockout, 46 mm offset for 29" wheel, 100 mm QR, 100 mm travel |
| Headset | Semi-Integrated, 1-1/8" |
| Stem | Bontrager Comp, 31.8 mm, Blendr compatible, 7-degree, 50 mm length |
| Bars | Bontrager alloy, 31.8 mm, 15 mm rise, 750 mm width |
| Front Brake | Tektro, 6-bolt, 160mm hydraulic disc |
| Rear Brake | Tektro, 6-bolt, 160mm hydraulic disc |
| Rear Mech | Shimano CUES U4000 |
| Shifters | Shimano U4000, 9-speed |
| Speed | 9 |
| Rims | Bontrager Connection, double-wall, 32-hole, 20 mm width, Schrader valve |
| Front Hub | Formula DC-20, alloy, 6-bolt, 5x100 mm QR |
| Rear Hub | Formula DC-22, alloy, 6-bolt, Shimano 8/9/10 freehub, 135x5 mm QR |
| Front Tyre | Bontrager XT3 Comp, wire bead, 30 tpi, 29x2.40" |
| Rear Tyre | Bontrager XT3 Comp, wire bead, 30 tpi, 29x2.40" |
| Seat Post | Bontrager alloy, 31.6 mm, 12 mm offset |
| Chainset | Prowheel C10Y-NW, 30T steel narrow-wide ring, 175 mm length |
| Bottom Bracket | VP BC73, 73 mm, threaded cartridge |
| Chain | Shimano LG500 |
| Cassette | Shimano LINKGLIDE LG300, 11-46, 9-speed |
| Pedals | VP-536 nylon platform |
Trek Marlin Gen 3 Sizing Guide
| Size | Height (cm) | Height (Feet / Inches) | Inseam (cm) | Inseam (Inches) |
|---|---|---|---|---|
| XS | 145 - 155 cm | 4'9" - 5'1" | 69 - 73 cm | 27" - 29" |
| S | 155 - 165 cm | 5'1" - 5'5" | 74 - 78 cm | 29" - 31" |
| M | 165 - 176 cm | 5'5" - 5'9" | 79 - 83 cm | 31" - 33" |
| ML | 173 - 180 cm | 5'8" - 5'11" | 81 - 86 cm | 32" - 34" |
| L | 177 - 188 cm | 5'10" - 6'2" | 84 - 89 cm | 33" - 35" |
| XL | 188 - 195 cm | 6'2" - 6'5" | 89 - 91 cm | 35" - 36" |
| XXL | 195 - 203 cm | 6'5" - 6'8" | 91 - 97 cm | 36" - 38" |
What size frame do I need if I am between sizes? - read here
Trek Marlin Gen 3 Geometry Chart
| Size | XS | S | M | ML | L | XL | XXL |
|---|---|---|---|---|---|---|---|
| Stack | 563 | 572 | 601 | 614 | 618 | 637 | 651 |
| Reach | 390 | 415 | 440 | 455 | 470 | 495 | 520 |
| Head Tube Length | 90 | 100 | 105 | 110 | 115 | 135 | 150 |
| Head Tube Angle | 66.5° | 66.5° | 66.5° | 66.5° | 66.5° | 66.5° | 66.5° |
| Bottom Bracket Height | 313 | 313 | 308 | 308 | 308 | 308 | 308 |
| Bottom Bracket Drop | 45 | 45 | 60 | 60 | 60 | 60 | 60 |
| Trail | 110 | 110 | 110 | 110 | 110 | 110 | 110 |
| Fork Rake/Offset | 42 | 42 | 46 | 46 | 46 | 46 | 46 |
| Chainstay Length | 433 | 433 | 438 | 438 | 438 | 438 | 438 |
| Wheelbase | 1092 | 1121 | 1153 | 1180 | 1197 | 1230 | 1261 |
| Top Tube Length (horizontal) | 551 | 579 | 615 | 631 | 647 | 678 | 707 |
| Standover Height | 658 | 692 | 747 | 759 | 771 | 791 | 816 |
| Seat Tube Length | 340 | 370 | 420 | 435 | 450 | 500 | 540 |
| Seat Tube Angle | 73.8° | 73.8° | 73.4° | 73.4° | 73.4° | 73.4° | 73.4° |
| Effective Seat Tube Angle | 74.0° | 74.0° | 74.0° | 74.0° | 74.0° | 74.0° | 74.0° |
All measurements are in mm unless otherwise stated.
The above table shows the standard geometry for the bicycle as shipped, other geometry configurations may be available with certain bikes. Please contact us via Live Chat to find out more.
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Trek Marlin 5 Gen 3 Mountain Bike 2025 - Hardtail MTB
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