The maximum speed of a bike with a 125cc engine can vary depending on several factors, including the bike's design, weight, aerodynamics, gearing, and overall condition. In general, most 125cc motorcycles have a top speed ranging from 55 to 70 miles per hour (90 to 113 kilometers per hour).
It's important to note that these figures are approximate and can vary based on the specific model of the motorcycle. Some motorcycles may have a slightly higher or lower top speed depending on their intended purpose. Additionally, factors such as rider weight, wind conditions, and terrain can also affect the top speed achieved by a motorcycle.
If you're considering purchasing a specific 125cc motorcycle, it's best to refer to the manufacturer's specifications or consult with the dealership for more accurate information regarding its top speed.