Marin San Quentin 3 27.5" Mountain Bike 2025 - Hardtail MTB
The Marin San Quentin 3 27.5" is built for aggressive trail riders who want a strong, capable hardtail ready for technical singletrack and jumps.
Key Features:
- Series 3 6061 aluminium frame, double-butted, trail-ready geometry
- Marzocchi Bomber Z2 fork with 140mm travel
- Shimano Deore 12-speed drivetrain for smooth, reliable shifting
- Shimano MT420 4-piston hydraulic disc brakes for confident stopping
- 27.5" wheels with Maxxis Assegai 2.5" tubeless-ready tyres
- X-Fusion Manic dropper post with size-specific travel
- Available with 0% APR finance
The Marin San Quentin 3 27.5" is made for riders who push hard on technical trails and want a hardtail that can handle the demands of modern trail riding. Designed in collaboration with freeride legend Matt Jones, the San Quentin 3 mixes dirt jump-inspired toughness with the capability to tackle challenging singletrack.
At the core is Marin’s Series 3 6061 aluminium frame, using double-butted tubing to keep weight low while delivering strength where it counts. Internal cable routing keeps everything tidy, and the trail geometry offers confidence on steep descents, technical sections, and flowy jumps.
Up front, the 140mm travel Marzocchi Bomber Z2 fork uses a Kabolt axle for added stiffness and precise control. Whether you're picking your way through rocky lines or sending bigger features, the San Quentin 3 gives you the support you need.
The Shimano Deore 12-speed drivetrain delivers smooth, crisp shifting with a wide 10-51T cassette, letting you climb efficiently and spin up for fast descents. Shimano MT420 4-piston hydraulic disc brakes offer reliable stopping power with excellent modulation, backed up by large 203mm and 180mm rotors for confidence on steep trails.
Rolling on 27.5” wheels with wide Maxxis Assegai 2.5” tyres, the San Quentin 3 grips across a variety of terrain, while the tubeless-ready rims allow for lower pressures to boost traction and comfort. The X-Fusion Manic dropper post with size-specific travel allows easy saddle adjustment on the fly, keeping you perfectly positioned as the trail changes.
The Marin San Quentin 3 27.5" brings together reliable components, aggressive geometry, and trail-tough design to handle everything from technical singletrack to bike park sessions.
Occasionally, without notice, manufacturers change product design and/or specifications.
| Frame | All New Series 3 6061 Aluminum, Double Butted Frame, Internal Cable Routing, 12x148mm Thru-Axle, 73mm Threaded BB |
| Fork | Marzocchi Bomber Z2, 110x15mm Boost Spacing, 140mm Travel, Kabolt Axle |
| Headset | FSA No 57E, Semi-Sealed Cartridge Bearings, 1 1/8" x 1 1/2” |
| Stem | Marin 3D Forged Alloy, 35mm |
| Bars | Marin Mini-Riser, 6061 Double Butted Aluminum, 780mm Width, 28mm Rise, 5º Up, 9º Back |
| Front Brake | Shimano MT420, 4-Piston Hydraulic Disc Brake, Metallic Pads, 203mm Rotor |
| Rear Brake | Shimano MT420, 4-Piston Hydraulic Disc Brake, Metallic Pads, 180mm Rotor |
| Brake Lever | Shimano MT4100 Hydraulic Lever, I-Spec EV Compatible |
| Rear Mech | Shimano Deore, 12-Speed, SGS |
| Shifters | Shimano Deore, 12-Speed, SL-7100R |
| Speed | 12 |
| Rims | Marin Aluminum Double Wall, Disc Specific, 29mm Inner, Sleeved Joint, 32H, Tubeless Compatible |
| Front Hub | Shimano HF-MT410B, 110x15mm, Disc |
| Rear Hub | Shimano HB-MT410B, 148x12mm, Disc, Microspline Freehub Body |
| Front Tyre | Maxxis Assegai, 27.5x2.5", 3C MAXX TERRA, EXO, Tubeless Compatible |
| Rear Tyre | Maxxis Assegai, 27.5x2.5", 3C MAXX TERRA, EXO, Tubeless Compatible |
| Seat Post | X-Fusion Manic, 1x Composite Remote, Size S 150mm Travel, All Other Sizes: 170mm Travel, 30.9mm |
| Saddle | Marin Speed Concept |
| Chainset | FSA Comet, Modular 1x, 32T Direct Mount Chainring, MegaTooth Technology, Boost Spacing |
| Bottom Bracket | Mego EXO 73mm BSA |
| Chain | KMC X-12 Silver and Black |
| Cassette | Shimano, Deore 12-Speed, 10-51T |
| Pedals | Nylon Platform |
San Quentin Sizing
See the table below to find the right size Marin San Quentin.
|
Height |
Size |
||||||
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4’8” / 143cm |
XXS |
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4’9” / 145cm |
XXS |
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4’10” / 148cm |
|
XS |
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4’11” / 150cm |
|
XS |
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5’0” / 152cm |
|
XS |
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5’1” / 155cm |
|
XS |
S |
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5’2” / 158cm |
|
|
S |
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5’3” / 160cm |
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|
S |
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5’4” / 163cm |
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|
S |
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5’5” / 165cm |
|
|
S |
M |
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5’6” / 168cm |
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|
M |
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5’7” / 170cm |
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|
M |
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5’8” / 173cm |
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|
M |
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5’9” / 175cm |
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|
M |
L |
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5’10” / 178cm |
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M |
L |
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5’11” / 180cm |
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|
L |
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6’0” / 183cm |
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|
L |
XL |
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6’1” / 185cm |
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L |
XL |
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6’2” / 188cm |
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|
XL |
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6’3” / 191cm |
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XL |
XXL |
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6’4” / 193cm |
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XXL |
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6’5” / 196cm |
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XXL |
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6’6” / 198cm |
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XXL |
Read our bike size guide for more information on sizing.
San Quentin Geometry
|
Size |
S |
M |
L |
XL |
|
Stack |
586.1 |
590.7 |
599.7 |
604.3 |
|
Reach
|
422 |
444 |
464 |
484 |
|
Head Tube Angle |
65 |
65 |
65 |
65 |
|
Head Tube Length |
105 |
110 |
120 |
125 |
|
Seat Tube Angle (Virtual) |
75 |
75 |
75 |
75 |
|
Seat Tube Angle (Actual) |
75 |
75 |
75 |
75 |
|
Seat Tube Length |
385 |
420 |
475 |
515 |
|
Top Tube (Actual) |
564 |
582 |
604 |
626 |
|
Top Tube (Effective) |
579.1 |
602.3 |
624.7 |
645.9 |
|
Bottom Bracket Height |
310 |
310 |
310 |
310 |
|
Bottom Bracket Drop |
50 |
50 |
50 |
50 |
|
Chain Stay |
425 |
425 |
425 |
425 |
|
Wheelbase |
1144.8 |
1168.9 |
1193.1 |
1215.3 |
|
Standover Height |
664 |
677 |
714 |
745 |
|
Fork Offset |
46 |
46 |
46 |
46 |
|
Seatpost Diameter |
30.9 |
30.9 |
30.9 |
30.9 |
|
Handlebar Width |
780 |
780 |
780 |
780 |
|
Stem Length |
45 |
45 |
45 |
45 |
|
Crank Length |
170 |
175 |
175 |
175 |
Read our Mountain Bike Geometry Explained guide for more information on MTB geometry.
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Marin San Quentin 3 27.5" Mountain Bike 2025 - Hardtail MTB
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