1992 K75 RT headlight bulb replacement.

[jiggseob]

My K75 low beam does not work, the place to start is the bulb.  Took off the inner liner of the fairing to get access to the back of the bulb.

Turns out the rubber boot across the back of the headlight housing is impossible to put on or get off, because the brackets holding the big upper fairing are tight to the headlight housing and not allowing space to remove or install that rubber boot.  The "gap" at the red arrow in the photo is about 1mm or less than 1/10".  Not able to work that rubber boot through that small gap.

This fairing - and its bracketing - is unique to the RT sub-model.  A question for anyone who has changed a headlight bulb in an RT:   Is something on my bike bent? Or is that the way they all are?  It will be almost impossible to get that rubber boot past that tiny gap and around the bottom of the bulb-opening in the back of the headlight housing.  This fairing mount bracket being somewhat bent would explain why I had such a Bart-Simpson of a time getting the mount points to line up on the fairing lowers and the radiator cowling.

[Duckbubbles]

Same problem on my '85 RS.  After I got it off, I trimmed the bottom of that rubber boot to allow it to be installed.  Still had major problems getting the bulb retaining ring back on.

Frank

[jiggseob]

It was the bulb, low-beam filament burnt out.  I took the wiring plug off the back, plugged in a known working bulb to the dangling socket, and turned the switch on and through both hi-beam and low-beam circuits.
I did get the bulb changed, by removing two (of four) bolts holding the fairing to the ends of the ;egs of the support bracket.  That allowed the fairing and the headlight housing to "flex" forward about 1/8", enough to work the rubber boot around both sides of the bottom of the headlight.
I do not want this process to be that difficult... hopefully its supposed to not be this difficult, and this winter I take the whole thing apart and un-bend things to provide clearance.
It could be that this headlight enclosure was actually designed this way.  There are aspects of design on this K75 that make me scratch my head; the battery hold-down bolts are phillips-head, but theres not space on top to put a phillips driver, much less a whack-it-with-a-hammer impact driver; much better to have hex or allen-head bolts there.
 

[sooprvylyn]

Bmw tends to do things in ways that make it hard for a home wrencher sometimes. I think that's on purpose.  Luckily there's clymers, ingenuity, and the internet.