The Merida MATTS J.20+ is a kids' mountain bike built for children between 109 and 129 cm who are ready to tackle real terrain. The TFS 6061 double-butted, technoformed aluminium frame keeps the weight down to around 9.5 kg — light enough for a child to handle with confidence, sturdy enough for trail use.
Where this bike really sets itself apart from budget kids' bikes is the braking system: Tektro Power DS-100HT hydraulic disc brakes (160 mm front, 140 mm rear) offer smooth, progressive stopping with minimal lever effort. That's a real advantage when a child is still learning to modulate speed. The rigid aluminium fork handles tyres up to 2.4", and the fitted CST Jet C1820 (20" × 2.4") tyres provide a comfortable ride over uneven surfaces.
The drivetrain keeps things simple with a single-chainring setup, a Shimano RD-M310 rear derailleur and a Shimano MF-TZ500 cassette (14–34 teeth) — fewer gears to think about, and a wide-enough range to tackle hills. The Merida Expert JR crankset uses 127 mm cranks, correctly proportioned for younger riders.
Thoughtful details add up: the flip-flop stem (Merida Expert CC, Ø 31.8 mm) lets you adjust the handlebar reach without swapping parts as your child grows, and the Merida Comp JR saddle is shaped specifically for young riders. This is a bike built to last a few seasons, not just one.
