Marin Alcatraz JR24 2025 - Kids Bike

Ready to launch into progression, the Marin Alcatraz JR24 brings big-bike feel to smaller riders. With a tough aluminium frame, dirt-ready geometry and single-speed simplicity, it's built for young shredders to rip, jump and repeat.
Key Features:
- Series 3 661 aluminium frame with dirt jump geometry and ISCG 5 tabs
- Marin Series 2 CrMo rigid fork, suspension corrected for 24” wheels
- Single-speed drivetrain with forged alloy 32T chainring
- Tektro MD-M280 mechanical disc brakes with 160mm rotors
- 24” wheels with Vee Rail 2.25” tyres for grip and flow
- Youth-optimised geometry with 360mm reach and 69° head angle
- Available with 0% APR finance
The Marin Alcatraz JR24 is purpose-built for junior dirt jumpers who are serious about sending it. Sharing the same DNA as the adult Alcatraz, this scaled-down version features the same butted aluminium tubing and aggressive geometry, perfect for young riders learning tricks, building skills, and developing confidence on dirt.
With a 360mm reach, 69° head angle and 72° seat angle, the Alcatraz JR24 delivers a stable yet responsive ride that’s tuned for manuals, berms and dirt doubles. The 369mm chainstays strike a great balance between flickability and control. A suspension-corrected Cro-Mo rigid fork gives a solid front end feel and helps young riders stay connected to the terrain.
Simple and low-maintenance, the single-speed drivetrain keeps things reliable and distraction-free, while the forged alloy cranks and 32T chainring are tough enough to take knocks. The external BB with sealed cartridge bearings ensures smooth pedalling session after session. Tektro mechanical disc brakes offer confident stopping in all conditions and are easy to service.
Rolling on wide 24” Marin custom rims and wrapped in grippy Vee Rail 2.25” tyres, this bike is ready for pump track laps, jump park missions or backyard sessions. Every component from the alloy riser bar to the DJ saddle has been chosen to suit smaller riders with big ambitions. The Marin Alcatraz JR24 is where fun, progression and durability meet for the next generation of dirt riders.
Occasionally, without notice, manufacturers change product design and/or specifications.
Frame | All New Series 3 661 Aluminum Frame, 24” Wheels, 135x1mm Horizontal Dropouts, 73mm Threaded BB, ISCG 5 Tabs |
Fork | Marin Series 2 Cro-Mo 24" Fork, Suspension Corrected, 100x9mm Drop Outs |
Headset | FSA No 57E, Semi-Sealed Cartridge Bearings, 1 1/8" x 1 1/2” |
Stem | Marin 3D Forged Alloy, 4mm |
Bars | Marin Riser, 661 Double Butted Aluminum, 38mm Rise, 75mm Width, 4º Up, 9º Back |
Front Brake | Tektro MD-M280 Mechanical Disc 160mm Rotor |
Rear Brake | Tektro MD-M280 Mechanical Disc 160mm Rotor |
Brake Lever | Tektro CL-330TS Alloy |
Speed | 1 |
Rims | Marin Custom Extrusion, 27mm Inner, Pinned Joint |
Front Hub | Forged Alloy, Bolt On 3/8th Axle, 100mm Spacing |
Rear Hub | Forged Alloy, 135x1mm, Bolt-On, Quad Sealed Bearings, Disc, 32H |
Spokes | 14g Black Stainless Steel |
Front Tyre | Vee Tire, Rail 24x2.25”, LSG Compound, Wire Bead |
Rear Tyre | Vee Tire, Rail 24x2.25”, LSG Compound, Wire Bead |
Seat Post | Marin Alloy, 30.9mm |
Saddle | Marin DJ Saddle |
Chainset | Marin Forged Alloy, Alloy 32T DM Chainring, 152mm Crank Length |
Bottom Bracket | External Sealed Cartridge Bearings |
Chain | KMC HL-1 |
Cassette | 14T Single Speed Cog |
Jump Bike Size guide
Jump bikes are designed and intended for Dirt jumps, street and skatepark riding. Not for riding any distance.
They primarily use a 26” wheel with the frame only available in one size, to suit riders taller than 4’5” or 137cm.
Some manufacturers offer a long or short length bike. Riders over 5’10” or 178cm will prefer the longer option.
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Marin Alcatraz JR24 2025 - Kids Bike
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