I’m happy I don’t know any better!Or an abundance of owners who don't know any better... frame flex is a real issue with heavy EBikes.
A step-through frame (also known as open frame or low-step frame) is a type of bicycle frame, often used for utility bicycles, with a low or absent top tube or cross-bar. Traditionally, bicycles with a step-through frame were known as "Ladies'", "Women's", or "Girls'", mainly for their advantage to riders wearing skirts or dresses. Bicycles with a high top tube (cross-bar), known as a diamond frame, were known as "Men's", "Gents'", or "Boys'". As a result of changing clothing styles since the late 20th century, descriptions that describe the frame style, rather than the presumed gender of the rider, are becoming increasingly common.
- less risk of stretching or ripping clothes when mounting the saddle
- the rider can wear a skirt (also requires a skirt guard and possibly a chain guard)
- very quick to mount and dismount, so is suitable for delivery bicycles, or any journey with many stops
- suitable for the elderly and others with restricted agility
- Heavier Compared to a traditional diamond frame consisting of two near-triangles, open or step-through frame designs must be designed with thicker gauge tubing, the use of additional gusseting members, and/or monocoque frame construction. These structural elements may add weight or cost over a traditional diamond design.
- Inattention to structural design can lead to excessive flexing, resulting in lower pedaling efficiency and reduced frame life.
- Fewer places to mount accessories, e.g. an air pump or water-bottle.
- More difficult to carry around off the ground due to the sloping tube near the bicycle's center of gravity, e.g. carrying it up stairs, or lifting to hang it for maintenance.