You can't ride with it.
While inconspicuous to the non-mechanic's eye, the star nut plays a vital role -- it sets the preload for headset bearings. Believe us, when you purchase a new fork, cutting the steerer tube is only one step along the path to installation. In fact, unless completely butchered, the cut falls more towards the category of fit. However, setting a Star Nut like this quality Cane Creek Insert is essential for function.
The Cane Creek Star Nut Insert is available in one color and is only compatible with 1-1/8in steerer tubes.