Generally you should be good with a bike that has a frame size of 17 19 inches.
Mens bike frame sizes inches.
Merida s road bikes go through s s m m l and l.
Imagine your leg inseam is 74cm then the best frame sizes for you are.
Consider the bike type.
If all three have a 15 frame there will be a height difference between them due to their wheel size.
The tables below show the frame size that best suits your height.
51 cm mountain bike.
49 cm road bike.
Bike frames are measured from the middle of their bottom bracket to the end of their seat tube.
You may find both units in the description of the bike.
You can find them with 26 wheels 27 5 wheels or 29 wheels.
That s a system used for some road bikes too.
The deciding factor for the size of a bicycle is the frame in particular the seat post the distance from the center of the bottom bracket to the top of the seat post.
That s not true of mountain bikes where the frame size is usually marked s m l etc.
Mountains bikes now come in three different wheel sizes.
The kind of bike you should have depends on your preferred riding style if you enjoy riding on paved surfaces and also off road then a hardtail mountain bike with a 29 wheels is something you will enjoy.
First consider what kind of bike you want sizing varies greatly between road and mountain bikes as well as between men s and women s models and even between.