Hi, Kirk here.

I appeared to have stepped in it good this time.

Just bought an 85 K100 that until 1995 was a well loved riding machine. As I understand the original owner had an accident around then that precluded him from riding and he let it sit outside as motivation to get better and back on the bike...

I have a pretty good paperwork trail up till about then.  Regular service and 9000 miles was the last documented service at Bob's BMW... It now sits at 9600 miles

Of course after sitting out for untold time the seat is a rusty semblance of a seat which will be the first thing tossed into the Bin.  There are lots of corroded fasteners and there is a lot of surface rust on the exposed frame, but I bought this as a project bike.

   

The first project will be getting the gas tank open as it appears that the key will not go all the way in.  The switch gear on the bars is all white from the elements.

My big concern though is the motor. My "friend" that I bought this from bought it from the original owner around three months ago. He sold it to me when he realized that he had too many other projects to tackle this one.  

So back to the motor.  He said that it turned by hand when in gear so it probably is not frozen.  I just want to treat the cylinders with something So that while I am rehabbing the rest of the bike (greasing all the splines, etc) the motor will not be going further downhill...

I wanted a project bike and this looks like a largeish one.  I have not decided on a path yet, besides going through all the mechanicals and making sure there is not a killer lurking in the old girl...

So. That is my intro post...  now the work begins...

Sounds like you have quite a project ahead of you.

Gas cap: Fill the lock with penetrating oil and let it sit. BMW put some kind of thick grease in the lock cores and it gets old and hard over the years.

I built my K75 around a spare engine that had been sitting for an unknown number of years.  I was a little concerned that the cylinders/pistons might be dry for the first startup so I sprayed fogging oil into the cylinders.

There may be some "better" oil or whatever for the task but I had some on hand and it's aerosol so that's what I used.

duck wrote:Sounds like you have quite a project ahead of you.

Gas cap: Fill the lock with penetrating oil and let it sit. BMW put some kind of thick grease in the lock cores and it gets old and hard over the years.

I built my K75 around a spare engine that had been sitting for an unknown number of years.  I was a little concerned that the cylinders/pistons might be dry for the first startup so I sprayed fogging oil into the cylinders.

There may be some "better" oil or whatever for the task but I had some on hand and it's aerosol so that's what I used.

Well turns out the gas cap was either unlocked or something else went bad with the lock because after fiddling with it for a while I was able to just push down and lift the cap up...  tank actually looks pretty good inside, fuelpump seal is knackered and all of the fuel pump nuts are rusted.

Seat is pulled off now as it just crumbled once it was opened up,  had to get the locking latch out as it was no longer attached to anything.  

Is there an easy way to drain the cooling system?

Hi there,

This might be useful to you for opening the tank:-

https://www.k100-forum.com/t9469-open-a-petrol-tank-cap-which-has-a-broken-lock

Good luck with the project,
Paul.

If the bike still has the original gas cap then (if memory serves, I haven't seen one for a few years) those earlier ones could be left unlocked.

At the front bottom of the engine is the water/oil pump. Remove the plug on the bottom to drain the cooling system. It helps if you pull the tank off first and remove the radiator cap.

A good way to think of K bikes is that they are essentially just a small car on two wheels.

duck wrote:If the bike still has the original gas cap then (if memory serves, I haven't seen one for a few years) those earlier ones could be left unlocked.

At the front bottom of the engine is the water/oil pump. Remove the plug on the bottom to drain the cooling system. It helps if you pull the tank off first and remove the radiator cap.

A good way to think of K bikes is that they are essentially just a small car on two wheels.

This bike had its cap replaced under warranty (according to the paperwork) the cap has a push button which the key fits into.  After I fiddled with it for a while I pushed the button...   Doh...

Here's what an early one looks like:



The later ones look like this and require a key to open every time:

duck wrote:Here's what an early one looks like:



The later ones look like this and require a key to open every time:

In that case it is an early one...  thanks for the photo.

Down the rabbit hole I have gone...

the last time it was loved, photo found in the boot with the manual and tool kit...


And 22 years later...





And the paint code...

went to Bob's BMW today.  Just looking for the some misc parts like fuel hose clamps, clutch bolts, etc.  They had every part I asked for in stock...  I was amazed...  I now have the swingarm boot, clutch boot.  They even had the handlebar switch gear...  I was not expecting to have this kind of spare parts service on a 32 year old bike...  

Of course I now have more money in parts than I paid for the bike...

Kirkster wrote:Of course I now have more money in parts than I paid for the bike...

Well thats a given. What were you thinking:roll: And don't even think about the hours you will spend restoring it. I am almost 12 months into a K1 restoration that had spent 4 to 5 years outside under a tarp before I got my mitts on it. Looked very similar to the photos you've posted...

I'm jealous,
Mine was nowhere near as "rested" as that and it still took nearly years to bring back to life, enjoy.
Tinkering with bikes stops you Tinkering with other women, that's what I tell the wife when I need a bit for the Ks.