Hello all....
New on this forum but been building and racing motorcycles since 1968.. Yeah I'm "getting up there" but still building and riding bikes...
A friend finally "hung up his spurs" at the age of 80 and pretty much gave me his 1985 K100RT with only 223,000 miles on it. Tom bought the bike in 1992 with only 4,200 miles on it and proceeded to pretty much live on it for the next twenty years. Tom was an "Adventure Rider" way before anyone had used the term. When he decided to quit riding the K I asked him if he'd rather see if BMW wanted the bike for their museum.. He replied "You'll have more fun with it". It's a testament to BMW longevity in that Tom had ridden it in 49 states, Canada and Mexico and only did regular services on it and an occasional minor repair. The bike was NEVER even washed much less degreased and looked more like a farm implement than a motorcycle. Even the paint on the frame is gone. I have every receipt going back to 1992 and I documented the bikes condition in detail with about 200 photos. The fiberglass was cracked in so many places I decided to just trash it and keep all the brackets. It even had a collection of dead rodents in a couple places. But, it still ran when I picked it up. I've pulled all of the plastic and fiberglass off and power washed it before I let it into my shop. It was truely a "rat bike". I've restored more than a dozen "barn finds" over the last 40 years.. HD's, Henderson, Excelsior, Triumphs, Boxers, Indians, Guzzi's, Vintage Japanese and even a Ner-A-Car. Whenever parts or money or both are in short supply I've "Bobbed" them. This K100 is a definite candidate for minimalism...
I plan on powder coating the frame, wheels and fork tubes black. I'd do the same on all of the engine but..... I may not even need to open the engine up.. It doesn't leak anywhere and the compression seems okay. The throttle bodies look like the insides of a 1985 VW K-Jet Tronic intake manifold... Lots of nasty grease and carbon so I'll probably do a "top end" on it with rings, valves, seal and gaskets and o-rings... glass bead blast everything but the crankcase and reinstall it.. I'll probably Plasti-Gauge the main and rod bearings just out of curiosity... 
Only frame mods will be to trim the fairing tabs and cut, reduce and tilt the rear frame section up to accept an aluminum cafe style seat pan with cowl.
To save $ I'm installing a 7" Honda CB750 headlamp with HID and an EMGO cafe fairing since those remind me of the Luftmeister on my old R80 and I can hide the giant gauge cluster in it. Z-bars will finish the front end mods. 
Questions... (More likely to come).
1: Anyone know of a vendor that sells rebuilt final drives from cores? I own my own machine shop but I'd rather farm the final drive out to someone that can 'do them blindfolded'. The "AX" bearing sounds & feels like it's toast.
2: Compression...
My COLD readings are: 1=195 psi 2=175 psi 3=180 psi 4=190 psi
My HOT readings are:   1=140 psi 2=95 psi 3=95 psi 4=135 psi
Sound about right?
Hopefully new rings will be all it needs. I saw a very slow leak down on the two center cylinders and hopefully rebuilding the head and just a light lapping in of the valves will be all that's needed..
I live about an hour's drive from Galen Perry's BMW bone yard so I may go pickin in the next few weeks...
I want to get all of the prep work done so I can just do reassembly when the snow flies...
It's winter therapy.
Thanks all....

Welcome to the forum.

That's a great story and one we all love to hear.

A K is definitely not just another bike. Its a new way of life.

Just buy a used final drive on Fleabay.  

Since you're doing the cafe thing, you might want to consider putting a 32/10 K75 final drive on it.  You get about 15% more torque that way.  I recently did this to my K100 and am happy with the results. (K75s came with either disc or drum read brakes so make sure you get a disc final drive. Avoid K75C final drives as those all had drum brake final drives.)

Welcome to the form, as I was told several times during my intro post,  photos....we love photos....

Cheers.

Dave.

Hi Stilbo. Welcome to the forum.
There's quite a story in that ol' girl of yours. Hope we get to see some of those pics you've taken and more of the resto and mods as your project progresses.

Will be stripping my RT down also but to complete naked. Would like to keep it pretty straight tho. Been looking at lots of K mods over the last few months to get some ideas. I'd like to keep the lines and style of this great machine but sport it up.

Cheers

Thanks for that tip Duck! Galen Perry has K100 & K75 final drives so I'll definately look for the lower ratio... This K has seen enough touring in it's lifetime. The low ratio will be perfect for the twisties.
Kafe... Pics coming up... I hope.

Wow!

Reassemble it, stick it in a glass case and charge people to see it...

I love the black tape over the idiot lights!   

Great to hear that you will be putting it back on the road too.

OMG!

It will be interesting to see this old girl when shen get out of the beauty salon.   

Stilbo wrote:Only frame mods will be to trim the fairing tabs and cut, reduce and tilt the rear frame section up to accept an aluminum cafe style seat pan with cowl.

Just my opinion but chopping its arse off will destroy its style and beauty. There are lots of good mods that have retained the seat frame to keep it in tune with '80s cafe/racer design. IMO 'bobbing is a more recent fad.
There are some nice duck-tail seat cowls worth considering. Check this forum.
https://www.k100-forum.com/t5707-ned-s-ride-1986-k100rs
The duck-tail in that forum would look awesome on a cafe racer. The only catch is they're hard to get and pretty $$y

Also... for interest... http://www.landbridge.net.au/K1004.html

Just my opinion
Cheers

welcome stilbo 

this looks interresting , i will be watching   .

k-rider

It's not Kafe, but this the rear end treatment I like.  It's what I'll be doing with my Rat when I finally start it.



I'm not against cutting or modding the rear frame, but I hate those slim seats that are nothing more than a bit of board, 1/2" of foam padding at most and a brown "leather" cover(most would be vinyl and the owner doesnt know the difference).  They are all absolutely useless. I guess just OK for the pose run to the coffee shop.

Al

Hi Al
Yup. That's a nice mod. Not so much the scrambler but I really like the front and the matt black really does it for me.
I plan to keep the classic K tail and modify the seat to give it a longer faux duck tail appearance with well padded single seat. This will be then swapped when needed with the original 2-up seat... not that I'll need it much at all. I can never find anyone (lady) who wants to come for a spin with me. I was approached recently in the carpark by a lady in her mid 80s who struck up a reasonably lengthy conversation about BMWs and the German quality. I offered to take her for a spin but she said that when she was 20 a young guy pillioned her from Sydney to Wollongong (probably a 2 or 3 hr trip back then) and she was "glad to get off the damn thing". 
Oh well, I guess I'll just keep trying.