You need to use the Following for that ::
<a href="@Url.Content("~/Bike/")">Home</a>
<ul>
@foreach (var item in @ViewBag.Menu)
{
<li>
<a href="@Url.Content("~/Bike/Categories/"+item.ID+"?name="+item.Name+"&class=image")">@item.Name</a>
</li>
}
</ul>
Because the ViewBag you have made contains multiple Entries(i.e. Enumerable)
ViewBag.Menu = BikesDB.ProductSubcategories
.Where(m => m.isSelected == true).AsEnumerable()
.Select(p => new Bike {
Id = p.ProductSubcategoryID,
Name = p.NameofBike
});