What's the white plastic cap on the wire end of an X5?

[CGameProgrammer]

The wire end of the Crystalyte motor has a white plastic sleeve around the axle, with a removable white plastic cap at the end. What is this for? Theoretical weatherproofing? My cap is very cracked from tightening the large nut against it and it's basically worthless now.

 

[Ypedal]

The original idea was to protect the wire from sharp edges on the axle.. and to protect the paint on your bike frame.. both of with it does a miserable job .....

Can be disregarded, just make sure you don't have the wires rubbing on a very sharp edge at the exit point of the hub.