I recently bought a K100RS, of course it needs work because that is what I always find. a good deal on someone else's project. So I brought the bike home in the middle of February and rolled it off the truck right into the garage. I started looking it over, getting familiar with my new toy. I needed to fix the final drive, the PO had taken it apart but had not put it back together properly. I have had a few bikes, recently sold my R60/6 to buy the K bike. So I decide the time has come to tear into the final drive and see what parts I need to buy. I positioned the bike in the work area and after rocking the bike up onto the center stand it sat there for a minute and then started to list to the left, like it was on soft dirt and not a concrete floor. And yes you got it, the center stand crumpled. It was a slow roll, The bike never went down, I caught it, balancing all 536 pounds from the wrong side of the bike. I stood there for a minute and then remembered to put the kickstand down. The curved tube center stand which as stock on the 87 was 30 years old, had served it's useful life and now the left leg was sheered off, still dangling by a toothpick size shred of metal. A couple wiggles and the offending broke leg was completely off. What did I do? I rushed into the house and opened up ebay, looking for replacements. Well I do recall reading in this forum that the stand will eventually break and the upgrade was better than just replacing it with the same old same old. I did not buy the stand that minute, I gave it a few hours. The thing I recall was someone said any K bike stand will work, so I found a good priced and decent looking K1200 stand. Unfortunately I did not recall the part which said the mounting bracket was different and would have to be swapped out. Well honestly I did read the one about the guy who was still running one with only 2 bolts but that may have been while I was waiting for this one to come in the mail. Of course when I open the box and try to bolt it on I start swearing because it won't fit. So I can answer some questions I have seen, no the K1200 stand is not a direct bolt in, but it does fit the same pivot points. Then I discover the part where it says the legs are too short. Damn. So I start thinking about what to do about it, everything from welding plate steel, to mounting hockey pucks, (but I'm not Canadian so I can't do that), and I was going to Frankenstein some bracket.
The bushings on the pivots look good, the bolts are straight. The advantage of using the K1200 mounting plate is the kickstand and stops will be in the right place, the K100 plate did not stop the center stand from hitting the exhaust and the kickstand springs mounted on the top side. The new kickstand is thicker metal as well.
Then it hits me. I found apiece of plate steel on the garage floor, (really) not expecting everyone to have such things lying around but I consider myself lucky. The first thing is to see it it will clear the mounting place without too much trimming. After several trips to the hardware store for M10x1.50 bolts of various lengths I have enough options to proceed. More trimming with the dremel on the bracket, and after drilling some holes in the steel I have a close fit. I used both the original K100 bracket and the K1200 bracket as a template to drill all 6 holes as needed, the front two are the same on both brackets. I ran short bolts up to mount the plate from the middle holes to the the 2 rear transmission mount holes, and had to grind a flat side on the heads of the rearmost bolts, several tries and it all fit together like a dream. No welding required.

IIRC TWB said that you need 19mm spacers to fit a K1200 stand to a K100. The K1100 stand is a direct fit replacement; fitting a K1100 stand is one mod that most of us have done.

The down side of the K1100 stand:

When it failed like so many before it, I replaced the original stand on my K100 with the K1100 one.

Twice now, bike on centre stand in the back yard, rain came down, ground softened. The right side of the stand sinks into the ground (left remains supported by the lifting lever) and the bike is on its side. Last time making a small dent in the tank from coming into contact with a lawnmower on its way down.

Should have learned after the first time - hard surfaces only!

Bill

I once played with a K75 center stand of a friend. The bike had been lowered because of her being a short lady and I though that cutting the stand be 3/8" would be easy. NOT! This is not an easy fix and I would never try to do that again. As Day said, buy a K1100 complete stand (Side and center) and do a straight replacement. You cannot put a K100 side stand on a K1100 center stand without modifications and this is why I say "Buy a complete set and sell the K12 back on Ebay"