I stripped the bike down, & replaced the clutch plate, O ring, thrust washer & nut, put in new housing bolts, also replaced rear engine main seal(sits behind clutch flywheel), gearbox input & output seals, plus output to drive shaft seal, the 3 gearbox seals were leaking, could not be certain about rear engine mainseal, so changed it anyway.
Slave cylinder ok, so left alone, drilled weep hole, while bike in bits did lots of cleaning, greasing & tidying up, changed out coolant & flushed system.
Before anyone asks, i did not take photos, if you saw the state of my garage you would understand, its not quite up to the spacious well lit standards you seem to have in America, i carried out work on cold concrete floor, as i could not justify the cost of a lift.
The reason for carrying out work was a slipping clutch, when it was stripped down the reasons were obvious, ie leaking fluid, but upon close inspection all clutch items were in excellent condition, the friction plate was hardly worn, when compared to the new one, although i replaced it, i feel it would probably been ok if i had just cleaned it!!.
The bike is a 2003 with 31000 miles, i ride carefully & its nearly all motorway miles, so it gets an easy life.
When i refitted the clutch, i did not use a mandrel to align it, instead i aligned it using an allen key, the width of which was an interference fit between the friction plate hub outer edge, & the cover plate inner edge, i worked at this until the allen key was a sliding fit all around the hub, ie exact dead centre.
I have used the bike for approx 200 miles since work completed, the vibration band at 4500rpm(approx), has been greatly reduced, the bike feels much smoother, i did find an exhaust leak on no 3 exhaust port which i cured when the exhaust gaskets were replaced, but it was a very minor one.
I do wonder, if the clutches are not being properly centred on initial installation, ie possible generous tolerances, if this would allow for a minor eccentric wear ot the seals??, reason for this train of thought being due to apparent big reduction in vibration at 4500rpm, a slight eccentric wear could result in seal failures, its just my thought on the subject, feel free to blow it out of the water!
Have also noticed that average fuel consumption up, approx 52 mpg before now approx 56mpg (uk gallons).
Would like to say that without the advice on this forum, i would not have attempted task, it made life easier, i found that between the BMW manual & advice here the task was ok, actually it was an utter swine, but manageable, so to all the contibutors-thankyou-
PS-Sorry but before anyone asks, i forgot to take the size of the allen key i used to centre the clutch, & it is too late now, as they all look the same in the toolbox.