What size bike for 105cm boy

For a 105 cm boy, start by comparing 14-inch and 16-inch bikes. His height fits both XBikes ranges, so measure his inseam and check real-world control before choosing.

The direct size answer

At 105 cm tall, a child falls within the XBikes starting ranges for both a 14 Inch bike, listed for 94–114 cm, and a 16 Inch bike, listed for 102–122 cm. That overlap does not mean the two sizes fit equally well. It means height alone cannot settle the choice.

A 14 Inch bike is usually the first size to try when the rider is less confident, has a shorter inseam or feels stretched on a larger frame. A 16 Inch bike may be relevant if he can comfortably stand over it, reach its controls and steer without strain. Do not choose 16 Inch merely to leave room for growth.

What to measure before shopping

Measure the child barefoot or in the shoes he will normally wear while riding. Record his current standing height rather than relying on an old measurement or age.

Next, measure his inseam. Have him stand upright with his feet slightly apart, then measure from the floor to the top of the inside leg. The useful comparison is between that measurement and the stand-over clearance and minimum saddle position of the exact bicycle. Those product dimensions are not supplied here, so check the product manual or confirm them with the seller.

Age is secondary. The XBikes starting points list 14 Inch for ages 3–6 and 16 Inch for ages 4–7, but a child’s proportions, reach and confidence determine whether either bike actually fits.

Compare the two likely wheel sizes

The supplied catalog option is useful because the XJD Boys & Girls BMX Bike with Training Wheels, 12/14/16" – Blue has 12 Inch, 14 Inch and 16 Inch SKU labels. For this 105 cm rider, its 14 Inch and 16 Inch versions provide the relevant comparison; its 12 Inch version falls outside the XBikes height starting point.

• XJD Boys & Girls BMX Bike with Training Wheels, 12/14/16" – Blue

  Available in 12 Inch, 14 Inch and 16 Inch labels. For a 105 cm rider, compare its 14 Inch and 16 Inch versions through an individual fit check; the 12 Inch version is below the supplied height range.

How to perform the fit check

Have the child try each candidate bicycle rather than judging from wheel size alone. Begin with these checks:

1. Stand-over: Ask him to straddle the bicycle with both feet flat on the ground. He should not be forced onto tiptoes or pressed uncomfortably against the frame.
2. Saddle position: Confirm that the saddle can be adjusted for a stable starting position while staying within the limits marked by the manufacturer.
3. Reach: With his hands in the riding position, he should not have to lock his elbows, lean excessively or slide forward to reach.
4. Brake control: If the bicycle has hand controls, verify that he can reach and operate them confidently. Do not assume their type or adjustment from the wheel-size label.
5. Handling: Let him start, stop, steer and turn in a controlled area. Watch for wobbling caused by struggling with the bicycle’s size rather than ordinary beginner uncertainty.

If the 16 Inch version compromises any of these points while the 14 Inch version does not, choose 14 Inch. If both fit, compare which one he controls more naturally now. A larger bicycle that he will eventually grow into is not the right fit today.

Where training wheels fit into the decision

The catalog title identifies the XJD Boys & Girls BMX Bike with Training Wheels, 12/14/16" – Blue as a kids’ BMX bike with training wheels. That feature may be relevant to a rider who still needs that form of support, but it does not correct an oversized frame, excessive reach or inaccessible controls.

Fit the bicycle first, then consider the child’s current balance and confidence. For assembly, adjustment, compatibility, maintenance, load limits and torque requirements, follow the manual for the exact SKU or use a qualified bicycle mechanic; those details are not included in the supplied catalog facts.

What to do next

Measure height and inseam, then arrange a side-by-side try of 14 Inch and 16 Inch versions where possible. Bring the helmet he will use: it must fit properly, sit level and have its straps adjusted according to the helmet manufacturer’s instructions.

For a boy measuring exactly 105 cm, reject the 12 Inch option under the supplied height standard. Choose between 14 Inch and 16 Inch only after he demonstrates comfortable stand-over, easy reach, reliable brake control and confident steering; if 16 Inch feels stretched, select 14 Inch now.