Telelever bolt cap query?

[cartejo5]

Evening folks, well as I work my through a recently aqquired project iv'e discovered parts number 7, 8 and 9 are missing as illustrated below. I know they are reffered to as bolt caps or covers can anyone tell me what their real function is and also more importantly are they needed?

Many thanks
John

http://www.realoem.com/bmw/enUS/showparts?id=0401-EUR-05-2001-259R-BMW-R_850_R_94_0401,0406_&diagId=31_0336

 

[cartejo5]

 

[Stujw70]

The seem to do a good job of keeping all the water and road crap out of the bearings