2025 San Quentin 20"

San Quentin 20"

See this bike in a different color:

White/Black

Price: $699.00 (USD)^*
Suspension: SR Suntour XCM 24 BOOST, 80mm Travel, 110mm Axle Spacing
Wheel Size: 20"
Frame: Aluminum

Size Range: One Size

Size	Rider height range
ONE SIZE	3'8" to 4'4"

Manufacturer’s suggested retail price may not include additional shipping or preparation charges and does not include applicable US sales tax. Please contact your local Marin dealer for a quote.

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We took our Matt Jones-inspired Marin San Quentin and shrunk it down to fit 20” wheels. It's the perfect bike for kids who are ready for their first proper, hardcore hardtail mountain bike.

The Marin San Quentin 20”, just like the big kid’s version, shreds the boundaries of the mountain bike genres - doing it all with a huge splash of big air, speed and style.

Designed with the input of freeride legend Matt Jones, the San Quentin takes the DNA of our dirt-jumping Alcatraz and mutates it into a go-further and faster all-round, hardcore hardtail. The San Quentin 20” will feel just like a ‘grown up’ mountain bike to your little ripper, built with a stout Series 2 aluminum frame, 20” wheels, an SR Suntour XCM suspension fork, 8-speed Shimano drivetrain and kid’s specific hydraulic disc brakes.

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Gallery
Specifications
Geometry
Technology
Service

Gallery

Specifications

Frame

Series 2 6061 Aluminum, 20” Wheels, Disc Specific, 135mm Dropouts
Front Suspension

SR Suntour XCM 24 BOOST, 80mm Travel, 110mm Axle Spacing
Rim

Marin, Double Wall Alloy, 25mm Internal
Hub Rear

Forged Aluminum, 32H, Disc Specific
Hub Front

Forged Aluminum, 32H, Disc Specific
Spokes

14g Stainless Steel
Tires

Vee Tire Crown Gem, 20x2.6”, Wire Bead
Derailleur Rear

Shimano Altus
Derailleur Front

-
Shift Lever

Shimano Altus SL-M315, 8-Speed
Crankset

Forged Alloy, Narrow Wide 30T, 140mm
Bottom Bracket

Sealed Cartridge Bearings, Square Taper
Chain

KMC Z8
Cassette

Shimano 8-speed, 11-32T
Brakes Front

Tektro HD-J285 Kid's Specific Hydraulic Disc
Brakes Rear

Tektro HD-J285 Kid's Specific Hydraulic Disc
Brake Levers

Tektro Kid's Specific Short Reach Lever for Hydraulic Brake
Handlebar

Marin Riser, 31.8 clamp, 30mm Rise, 590mm Width
Stem

Marin Alloy, 35mm
Grips

Marin MTB
Headset

1-1/8" x 1-1/8" FSA No 10P
Seatpost

Marin Alloy, 30.9mm
Saddle

Marin Kids MTB
Pedals

Kids Specific Nylon Pedal

Specifications, pricing, and availability are subject to change without notice.

Geometry

	ONE SIZE
Stack	499
Reach	310
Head Tube Angle	65°
Head Tube Length	90
Seat Tube Angle	75°
Seat Tube Length	308
Top Tube Effective	443.4
BB Height	260
BB Drop	10
Chain Stay	340
Wheel Base	922
Stand Over Height	540
Fork Offset	40
SeatPost Diameter	30.9
Handlebar Width	590
Stem Length	35
Crank Length	140

All lengths in millimeters

Technology

San Quentin 24" in the English countryside

SERIES 2 ALUMINUM FRAME

San Quentin 24” and 20” both feature a Series 2 aluminum frame, with a tapered headtube, 3D forged dropouts, IS brake mounts, semi-internal cable routing and 135mm open dropouts.

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DIRT JUMP INSPIRED FRAME STYLE

Taking cues from the Alcatraz, as well as the full-size San Quentin lineup, the San Quentin 24” and 20” proved all the benefits of DJ style, with massive standover, slick frame tubes, and a hot paint job.

MODERN TRAIL GEOMETRY

A slack headtube angle paired with a steep seat tube angle creates a ride that will fly uphill, yet descend like it’s on rails. The balanced rider position is puts the rider weight between the wheels for steady climbing and handling on flats, while the slack front end helps to add higher speed stability through turns and rough patches.