Maintaining the Sales Order BOM 
Use
If you use a configurable material with a sales order BOM, you can only maintain the BOM components using the sales order BOM. After you have assigned values to the higher-level material in the BOM component of the sales order, you can continue with further characteristic value assignments, changes, or material deletion by proceeding as follows.
Procedure
Menu Path |
Logistics ® Production ® Master Data ® Bills of Material ® Bill of Material ® Order BOM ® Maintain (Multi-Level) |
Transaction Code |
CU51 |
Field |
Data |
Order |
Your order number |
Item |
10 |
Material |
P-501 |
You can now change the component quantity for component 500-900 or define a new item by marking it as a stock item.
Field |
Data |
Quantity |
3 |
Field |
Data |
Maximum working pressure (bar) |
5 |
Range |
01 |
Connection |
03 |
You now see that you can both configure shaft assembly 501-300 and assign characteristic values.

You could make additional changes to item 501-300, for example, adding a new item or changing the component quantity.