Author Topic: 1986 K75 to Cafe Racer  (Read 5096 times)

Offline Heezea

  • Motobrick Curious
  • Posts: 20
1986 K75 to Cafe Racer
« on: November 23, 2017, 10:58:51 AM »
Hey guys, just picked up my first bike ever, a 1986 K75. I'm hoping to turn her into a cafe racer (yes another one)! I'd like to post progress of the conversion here. For the past month or two I've been reading all the BMW forums and Motobrick is by far the best. The amount and quality of information is amazing. Hopefully this thread will add a little something. I had been looking at cafe racers and as soon as I saw a K75 I knew that's what it had to be. I think the angularity overall is just perfect, that angularity is expressed of course in the engine, plus the awesome design of the fuel tank, and carried right into the sweet wheel "spokes"; definitely a winning combo of hard lines that "spoke" to me.


The bike is running really well, starts right up, no funky sounds or noises, no hesitation, solid. The PO told me he changed all the fluids and lubed the spline drive. I believe him because he gave me the remaining tube of moly paste and he had done a lot of work to the bike. None the less, I will check over the fluids as I go. I think I'll end up changing them out through the conversion steps anyway. I'd like to do the work incrementally so I can drive a few times a month. But we'll see how I feel about multiple laps of assembly/disassembly as we progress.


I suppose a list of tasks I think are necessary are in order.
  • Remove all fairings and extra trim. This will be somewhat of an ongoing process but I did get all the major pieces off already. If anybody needs a piece, let me know. However, the parts have been painted white with moderate success, have had holes drilled in them to be zip tied to the frame, so they aren't exactly mint condition.
  • Get new tires. The tires have cracks in the walls so this is a priority. I like the look of the high-wall tires on the cafe racers so will need to figure out what to use. Unfortunately, I expect this will contradict my statement below about lowering the center of gravity.
  • Fabricate a seat.
  • Light mounts. Figure out how to mount the headlight and signals for intermediate stage. By intermediate I mean eventually I'd like to go to another setup but for driving around before that, I would like to keep things working.
  • Update to single gauge. This scares me, not good with electrical work.
  • Update bike stance. Mostly I'd like to lower the center of gravity. I'd also like to tuck in the front wheel so it's closer to the engine. I'm not sure if this can be done.
  • Update the handle bars. When looking from the rear of the bike, I'd like the handle bars to angle down 15 to 30 degrees. I'm thinking of using strap-ons as I thought that's what I saw used most successfully in some of the other build threads.
  • Update the controls. I'd like to have smaller simpler cleaner controls on the handle bars.
  • Update to pod air filters instead of air box.
  • Update paint. Thinking flat black for everything but the tank. The tank will probably be blue on top (really dig the XSR900 titanium blue) with some accents.
Inspiration: Love the color, love the lines.



More Inspiration: This is actually a K1100. The spoked wheels look cool but I think the originals are even cooler. However, this bike is pretty much perfect.



Coming home!



Fully dressed:



Getting nekkid!



  • Norfolk, VA
  • 1986 K75C

Offline Laitch

  • Faster than a speeding pullet
  • Administrator
  • ^ Quintessential Motobricker
  • Posts: 10153
Re: 1986 K75 to Cafe Racer
« Reply #1 on: November 23, 2017, 12:44:08 PM »
Update to pod air filters instead of air box.
The K75 has an air flow meter to help determine fuel rates that's upstream of all three throttle bodies. That and the L-Jetronic fuel injection control unit make problematic the usage of a separate pod filter for each throttle body. Removal of the air box and conversion to one pod filter for the air flow sensor is easily done.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles
I wept because I had no radials until I met a man who had no splines.

Offline rbm

  • ^ Quintessential Motobricker
  • Posts: 2283
Re: 1986 K75 to Cafe Racer
« Reply #2 on: November 23, 2017, 08:48:14 PM »
... or carbs.


  • Regards, Robert
Toronto, Ontario

1987 K75 - Build Blog @http://k75retro.blogspot.ca/

Offline Quiltzig

  • ^ Motobrick Curious
  • Posts: 99
  • K Guy
Re: 1986 K75 to Cafe Racer
« Reply #3 on: June 26, 2018, 12:16:42 AM »
How is your project coming along?
  • Hamilton - New Zealand
  • K75S
1987 K75S - cafe racer project
2016 R9T (wifes ride)
2004 K1200RS

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