By default setting, the minimum design radius will follow Arahan Teknik Jalan (ATJ) 8/86 or in software, you will see as JKR standard.
![image2](https://i0.wp.com/mes100.wpengine.com/wp-content/uploads/2018/01/image2.png?resize=981%2C109)
To enable the minimum radius to be edited, you can change the minimum radius standards at Parameters >> Analysis >> Design >> Change minimum radius standards to none.
![image1](https://i0.wp.com/mes100.wpengine.com/wp-content/uploads/2018/01/image1.png?resize=746%2C490)