Ahh gotcha. Meant no disrespect with my implication of your implication! Seems that that's not the issue for me (luckily). Although good to keep in mind as I actually have some experience with the relics of the past as you say. My mk2 golf left me stranded and wouldn't start for 7 months, went to 3 garages but no one could find the fault and all told me to scrap the car. That was my introduction to wrenching, and after 7 long months I found out about the distributor points, replaced them in 5 minutes for the massive cost of €7,49 and the car ran like a dream and has never left me stranded in the next 5 years dailying it (still use it every day).

While inspecting I actually found a tear in c4's intake hose. A new one should be coming tomorrow so hopefully that will fix it. I have some experience with lean bogs on my carburetted car but nothing this bad, but who knows.

I'm implying a fault in the ignition switch that is common in old Bricks could be occurring regardless of the battery's state of charge.

The contacts within it become corroded and need cleaning and lubrication, similar to distributor points in the relics that taught some of us early on. It starts out with an occasional miss and often ends up with a prolonged spell of roadside cursing in the middle of nowhere. When the fault occurs it acts like the switch has been turned off for a moment—the alternator bulb lights, the tach needle drops like a stone and then, PRESTO, everything is normal.

According to the website I've got one produced in the 2nd month of 1999. Makes a lot of sense since it was bought sometime in 2000 by the first owner. So it's one of the absolute last K1100s to be produced since according to this website the last VINs are from the 4th month of 1999! Interesting to see that they continued producing the LTs for 3 years longer than the RSs.

Do you know if I could decipher the actual build year from my VIN?

You seem to have an understanding of the Motronic/ABS variance by manufacturing year. The existence, appearance and location of some of the components also differ after '93.  If you want to try verification, put the last seven digits—or the only seven digits you have—into the serial number box at this site and let us know what comes up.

Welcome, Kevin!  Can you start a new thread about the running problem with all the details you can.  Then the brain trust can make some suggestions as the the cause and the cure.