There are several options to that question. If you're talking about frame size on a MTB, then 20" would be a large bike. If you're talking about 20" wheel size, then it's probably a BMX which is a fairly small bike.
The main differences between a 20-inch and a 24-inch BMX bike are the size of the wheels and frame. A 20-inch BMX bike is smaller and lighter, making it easier to maneuver and perform tricks. A 24-inch BMX bike is larger and provides more stability and speed, making it better for racing and riding on rough terrain.
The size of a child's bike ranges from a 12 inch wheel size for ages 2-5 to a 24 inch wheel size for youth ages. Usually a child with a height of 28-38 inches will need a 12 inch wheel size while a child that is 48-60 inches tall will need a wheel size of 20-24 inches.
For a 20-inch bike, you should use a 1/2 inch pitch chain with 1/8 inch width.
A 20 inch tire.
You can find a replacement 20-inch bike wheel for your bicycle at a local bike shop, online retailers such as Amazon or eBay, or at sporting goods stores that sell bike parts.
The weight limit for a 20-inch bike is typically around 200-250 pounds, but it can vary depending on the specific model and brand.
When purchasing a bike rim with a 20-inch diameter, consider the material, weight, durability, spoke count, and compatibility with your bike's brakes and tires.
The cost of replacing a 20-inch bike wheel can range from 20 to 50, depending on the quality and brand of the wheel.
Using a bike with 20-inch wheels for city commuting offers advantages such as increased maneuverability in tight spaces, easier acceleration from stops, and better portability when carrying or storing the bike.
When purchasing an electric 20-inch bike, consider the battery life, motor power, weight capacity, and overall build quality. These features will impact the performance, range, and durability of the bike.
The standard size and pitch of bike pedal threads are 9/16 inch and 20 threads per inch.
The standard size and pitch of a bike pedal thread is 9/16 inch with 20 threads per inch.