Depends on what size wheels the frame is made for. You could have an 18" that is meant for 20" BMX wheels, or 26" MTB wheels or 29er MTB wheels. Getting the wheel size wrong is unlikely to result in a nicely rideable bike.
Almost 100% definitely not.
the overall frame size. not specific to wheel size, as most mtb wheels are 26 inch.
No, you cannot put 24 wheels on a 26-inch bike. The wheel size must match the bike frame size for proper fit and function.
The size of bike wheels you should choose is typically based on your height. For adults, a general guideline is: 26-inch wheels for heights under 5'4" 27.5-inch wheels for heights between 5'4" and 5'7" 29-inch wheels for heights over 5'7" It's important to also consider your riding style and preferences when selecting wheel size.
The standard wheel size is a 16 inch wheels. There are options available for larger wheels, such as a 17 inch, 20 inch, and 22 inch wheels.
A 17-inch bike frame is considered a medium size for adults.
All "true" BMX bikes are built for 20" wheels, which makes them very similar in size.
The Genesis bike with 29-inch wheels has specifications including a frame size of 17 inches, 21-speed gears, front suspension, and disc brakes for reliable stopping power.
The front wheels are 19 inch and the rear wheels are 20 inch.
For 26 inch rims, you should use tires that are designed for 26 inch wheels. The tire size will typically be indicated on the sidewall of the tire, and it should match the rim size to ensure proper fit and performance.
In a 26-inch bike size chart, you can find information about the recommended frame size, suitable rider height, and inseam measurement for bikes with 26-inch wheels. This chart helps you choose the right bike size based on your height and inseam length.
When choosing a 20-inch bike frame size, consider your height, inseam length, riding style, and comfort preferences. A frame size that allows for proper leg extension while pedaling and a comfortable reach to the handlebars is important for a good fit.