Do I need only X4 cassette body or whole conversion kit SRAM XD for Novatec MTB wheels when going from Shim to SRAM XD?
You are surely asking about conversion kit listed on Novatec European e-shop shown in the picture below.
This conversion kit was meant for old batch of Novatec MTB wheels which were initially produced for Shimano usage only.
So, if you wanted to convert the wheels to SRAM XD you had to change also the axle suitable for SRAM, not just the cassette body (that’s why this kit was made).
Fortunately, the axle was upgraded later so it could take both Shim and SRAM XD.
Please check the drawing below and see which type of axle you have.
If you have NEW one, you don’t need the kit.
As you can see in this drawing, the difference between old and new axle is in shifted position of the flange by 3mm so thanks to that the axle goes now deeper into cassette body.
For this reason, the oil seal on cassette body has to be turned upside-down so that allows the axle to get deeper.
This picture below shows which oil seal (black rubber seal) I mean and how it should be positioned:
This picture shows both axles for your reference:
Video at the bottom shows the whole procedure of axle exchanging, but flipping the oil seal is not mentioned in there so don’t forget about it. If you don’t do it, the axle’s flange will interfere with oil seal causing some big friction and hub won’t turn smoothly (or will be blocked completely). Check out also the pfd in Documents section.