First pedal bikes

The first pedal bike is mostly a weight problem. Everything else — the colors, the graphics, the brand story — is decoration on top of one question: how much bike is your child being asked to manage?

The 16-inch bikes we researched range from 12.1 lb to 21.16 lb. Against a typical five-year-old at 39.8 lb, that is the difference between about 30% and about 53% of their own body weight. Scale the second figure to an adult and you get a 96 lb bicycle. Nobody would hand that to a beginner and expect enthusiasm.

The three specs that decide it

1. Weight

Aim for under a third of the child's body weight. It shows up in three places: getting moving from a standstill, lifting the bike upright after a tip-over, and the last ten minutes of a ride. The full arithmetic, with the CDC weight medians we used, is on why kids bikes are so heavy.

2. Minimum saddle height

Weight decides whether they can manage the bike; minimum saddle height decides whether they can ride it. Two 16-inch bikes here differ by 2.1 inches at the lowest setting, which at this scale is a whole size.

3. Brakes

Hand brakes with short-reach levers are what your child will use for the rest of their life. A coaster brake — stop by pedaling backwards — is easier on day one and a nuisance afterwards, because it blocks backpedaling to set the pedal position for a start. Guardian's single-lever SureStop is a third approach that removes the front-brake mistake entirely.

What this stage costs, honestly

The specialist bikes cost several times what a mass-market bike costs. The measurable difference is around 8 lb, usable brakes and published fit data. For a child who rides regularly that changes everything; for two laps of the driveway twice a summer it does not, and we would rather say so.

The route that gets you the light bike without the price is buying used — kids outgrow bikes long before they wear them out. Four checks tell you whether a used one is sound: buying a used kids bike.

Two pages work through that cost on specific bikes: our woom 3 (GO 3) review takes the 13 lb 16-inch apart figure by figure, and the best girls' bikes ranks six bikes from 12 to 20 inch on weight and published saddle range rather than on paint. The same job from the other side of the aisle — and what a suspension fork and knobby tires really cost in pounds — is best boys' bikes.

One warning if you are buying into a single brand at this stage: the fit ranges do not always join up. woom's GO 1 balance bike runs out at a 14.4 inch inseam and its GO 2 pedal bike does not start until 16, so a child in between fits neither — woom GO 1 vs GO 2 shows the gap and the three ways out of it.

What comes next

A 14-inch usually lasts a year, a 16-inch two or three. The move up is driven by fit, not by age — when the saddle is at its maximum and knees are hitting the bars, it is time. If the terrain has also started demanding gears, the answer is on when do kids need gears.