The specific rules and regulations regarding motorcycle licensing and testing can vary depending on the country or jurisdiction. It's important to consult your local motor vehicle department or licensing authority for accurate information.
In many places, motorcycle licensing tests are conducted on motorcycles that fall within a specific engine displacement range. For example, the test might require you to use a motorcycle with an engine size between 125cc and 500cc. In such cases, practicing on a 100cc bike may still be helpful as it allows you to gain experience and develop basic riding skills.
The handling characteristics and dynamics of a larger and more powerful motorcycle can be quite different from a smaller one. Therefore, practicing on a 100cc bike might not fully prepare you for the test if it requires you to ride a larger motorcycle.
To ensure you are well-prepared for your licensing test, it's best to adhere to any requirements or guidelines set by your local licensing authority. If possible, consider practicing on a motorcycle that is similar in size and power to the one you will be using for the test. This will help you become comfortable and confident in handling the specific motorcycle you'll be evaluated on.