Can anyone tell me what year the K75 got a rear disc brake?  

Was the drum brake any good?

The K75c always had a drum and the disc came with the K75s and a bit later the K75RT also had a disc.
The disc rear drive can be fitted to a c but you need the right footpeg plate to hold the master cylinder and a 17in rear wheel from a disc brake rear end.

The C model rear wheel is an R100 wheel and the drum is a beauty works well less trouble than the warped grooved seized disc's others have complained about from the K100 family, also of interest would be that hitting a really big pothole can dislodge the clips that hold the shoes inplace which will be noticed by a slight rasping noise as the wheel turns. If that happens then you can remove the wheel and reset the clip or if it gets damaged grab a new one. They are trouble free otherwise. If you go up a size in tyre then the 130 or 140 x 18 will make the bike understeer in the wet you will feel it for sure, they are sensitive little bikes

Cheers, thanks for that!

Which K75 has the most upright riding position?  I am pretty sure the S has the low sport bike stance, but what about the others?

There's also a K75/2 - naked with the 17" rear wheel and disc brake. Low seat and same bars as my 100/2.

Alheng wrote:
Which K75 has the most upright riding position?  

 As standard, the K75RT but fitting RT bars to K75C/K75 and K75S would do the same for the riding position. You'd need new (longer) cables though.

The K75C was renamed K75 at about the time that it got the disc rear brake and 18" rear wheel. Some importers chucked parts from the BMW extras list at the K75 and called it something else: BMW(NA) put a touring screen and panniers on the K75 and called it the K75T whereas BMW(Aus) seems to have resurrected the Boxer "stroke" or "slash" number nomenclature.

Many K75C and K75 models were produced in the low seat guise. It wasn't standard on either version. It was felt that vertically challenged buyers would probably opt for an unfaired machine but there are enough faired models with the low seat option to suggest that not all short-arsed owners were intimidated. 

MikeP meant disc brake with the 17inch wheel i reckon . As for the drum brake , i initially thought it felt "wooden " but not many K's down the road and I was happy with it . I don't recommend it as a test but 900kms in a day with ONLY the rear brake through the mountains of OZ and I love that drum brake.
G

Old age is a bugger. Yes I did mean 17" wheel with the disc version.

I remember the front hydraulics having an issue gordo ... easy fix ol mate

a mighty effort for sure

cheers

Yeah Chas that was a huge day makin the meet then the camaradie flowing that night , in the morning your spot on diagnosis ... wow that was a buzz ... so simple ..gunna tell that (again ) in my pic thread i got going today / yesterday ..WOW i feel so empowered , I put up pics !!!

Sorry guys , you won't shut me up for a while he he he .

Thanks folks. I'm starting to seriously look for one atm and most that I have come across are the older ones with the drum brake in the rear. I take it that parts would be about the same to source as the 100?

Here you are and a fair price http://www.gumtree.com.au/s-ad/gosnells/motorcycles/bmw-k75rt-abs-and-efi/1023964480

Yup saw that one and a few others but none have stood out yet.

That rt looks like its got the wrong battery covers on it

Yeah it has , many of the K75s came with a low seat and if they were put back to the standard seat hight then you took what you could find in the way of sidecovers.

This is straight from the 1988 sales brochure

Ah that would explain it. gotta love those sales brochures they look magic in them

So, was there ever an 18" disc brake rear wheel on either K75 of K100?

arbalest wrote:So, was there ever an 18" disc brake rear wheel on either K75 of K100?

According to MaxBMW's parts fiche, the 18" disc brake rear wheel was introduced as OEM on the '90–'92 K100RS 4-valve. Except for the drum brake C model, the K75 rear wheels were 17".

Thanks.