View Full Version : Need a K75 Transmission. . .

Dan Kearney
01-22-2004, 07:16 PM
Greetings All,

I took my 1987 K75 in to the dealer for a spline lube (First since I've owned it) and discovered that the splines on the input shaft are shot. Dealer says it'll cost a couple of grand to rebuild the transmission in order to replace the shaft.

So, I am in the market for a used transmission. My question is, what years and models can I scavenge from? Can I use K100 or K1100 transmissions?

I have one lead on a 1990 K75 transmission which the owner states has 175,000 miles on it but excellent splines. Any suggestions?


Dan K.

01-22-2004, 07:47 PM
I am rebuilding a wrecked K75 and have had excellent results in locating used parts on the Internet BMW Riders Marketplace website. Most users of the Marketplace are reliable people, and I have yet to have a negative experience in probably two dozen transactions, from small pieces up to and including a full RT fairing. Of course YMMV, but I think this is a good parts source.


You can scan the "for sale" ads or post a "parts wanted" ad. The ads are very well organized by type and also chronologically.

I am sure you can find what you need for much much less than the repair price you were quoted.

Dan Kearney
01-22-2004, 10:56 PM

Thanks for the info. I have used the marketplace many times with results similar to yours. As a matter of fact the tranny that I talk about in my original post is from there.

Have you got any idea about cross-model, or cross-year compatibility?


Dan K.

01-23-2004, 01:31 AM
How on earth can it cost "a couple grand" to replace an input shaft? Those things are like $300-400 brand new.

Check out this picture from the Clymer manual. It looks like the input shaft is easily replaceable. Can you find another dealer?

01-23-2004, 03:51 AM
I am not enough of a "K" expert to know for sure, but virtually all the parts I have replaced on my K75 rebuild project are compatible with the 1986 though 1990 K100 2-valve models. From time to time I have "borrowed" pieces from my project K75 and used them on my '88 K100LT. I even swapped the final drive temporarily from the 75 using it on the 100. A different ratio, but a direct bolt-up.

My educated guess is that the transmission from a 2-valve K100 will work on your K75. I don't know if they have the same gear ratios.

Any experts out there?

01-23-2004, 04:29 AM
Paging Mr. Eilenberger and Mr. Curry....

Dan Kearney
01-23-2004, 06:08 PM

I will be picking my K75 up at the dealer later today to get the full scoop from him. Off the top of my head I am willing to bet that the vast majority of that "couple of thousands of dollars" would be accountable to labor charges. It probably takes a number of hours to remove, disassemble, replace, reassemble and reinstall the trans. I've never done it, but that's my guess.

01-27-2004, 04:53 AM
Originally posted by KBasa
Paging Mr. Eilenberger and Mr. Curry....

Dan has contacted me directly on this - to summarize my advice - as far as that dealer - RUN AWAY RUN AWAY..

The dealer is estimating $450 labor and about $500 in parts to replace a clutch disk and install the used transmission. That's about 3 hours labor for a non-ABS model (and that's me doin' it) and mebbe $100 in parts.