Shopping Advice (scroll down past the advice to the products if you like)
Overview - These are for six to eight year olds who ride fair distances with their parents. They're a small bike for young riders, who will often gain no benefit from having gears without a fair bit of parental help in using them. And, because they have gears, they don't have the trusty coaster (back pedal) brake. So the rider also needs sufficient coordination and hand strength to use hand brakes. And Mum or Dad should regularly make sure the gears and brakes are working correctly. But if the family wants to rider 5, 10, 20km together, these bikes can be ideal.
Gears - They'll have five, six or seven gears. The gear range will be similar; more gears means smaller jumps between gears. Six and seven speed gears are more sophisticated than five speeds, and gear shifting will be smoother and easier.
Gear Levers - Small hands cope best with twist grip style gear levers. But they should be easy to turn; some can take a fair bit of force to change gear. We find Shimano branded twist-shifters to have a good, light action. Thumb-shifters are simple and reliable, but not as easy for small hands and uncertain riders.
Brakes - Most will come with V-brakes. These are powerful, so should give sufficient stopping power when operated by young hands.
Brake Levers - Make sure the brake lever reach is OK, so the rider can comfortably reach and operate the brake levers. Many brake levers have adjustable reach. Adjusting the lever reach will mean readjusting the brakes. It's difficult to adjust brakes to a very short reach lever; slight brake rub on the wheels can be difficult to avoid.
Weight - All else being equal, a lighter bike will be faster, easier and more enjoyable to ride than a heavier bike.
Tyres - If the bike will mostly be in the dirt, a knobbly, wide tyre will be good. If it'll usually be on sealed roads, consider a narrower, smoother tread tyre. If the bike doesn't have suitable tyres fitted, don't worry, they can easily be changed.
Bike Size - The rider not only needs to be able to stand comfortably over the frame with feet flat on the ground, they also need to be able to steer comfortably while seated. This will usually not be a problem on this size bike, but can be on the next size up.