Author Topic: What's the most stripped down K bike you've seen (that still works)  (Read 8770 times)

Offline oneplustwo

  • ^ Motobrick Curious
  • Posts: 109
I'm looking for inspiration for my build.  The Kappa looks amazing but it's so stripped down it doesn't actually run.  So I'm looking for something that is functional.


I think the biggest challenge is figuring out how to minimize the visual impact of the intake.  Perhaps trim the chamber above the throttle bodies down a bit and then add a cone filter instead of the large intake box?  I know there may be some performance hit, but I'm ok with that.  I already plan on a smaller battery and relocating some of the electronics.  Any other thoughts or perhaps links to existing minimalist builds?



  • San Francisco
  • 1990 K75S (in 1000 pieces)

Offline Martin

  • ^ Quintessential Motobricker
  • Posts: 4475
The MAF resides in the air box  and unless you go to extreme lengths and substitute with another fuel system you will have to live with the MAF. You can get rid of the air filter housing leave the MAF and put a single cone filter on it.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline oneplustwo

  • ^ Motobrick Curious
  • Posts: 109
Yes, I figured I would need to keep the MAF sensor.  This might be apparent to me once I dig into it more, but does the sensor take up a lot of room in the air box?  What I'm getting to is whether I could modify the box and make it smaller without adversely impacting the functionality of the MAF.
  • San Francisco
  • 1990 K75S (in 1000 pieces)

Offline Martin

  • ^ Quintessential Motobricker
  • Posts: 4475
You can get rid of the air filter housing leave the MAF and put a single cone filter on it.
You will have to put a bracket on it to stop it bouncing around.  A few guys have gone down this route and will probably post a picture,  Others have gone to a Mega Squirt injection system others have gone to a carburettor, or carburettors. Doing a search will on this site will uncover what's previously been done.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline oneplustwo

  • ^ Motobrick Curious
  • Posts: 109
I tried a search and came across some of the more involved options.  But didn't see anything using the existing FI system.  I'll try some more search terms. 


Is there anything else that can be "deleted" from the bike beyond the aesthetic items?  I'm looking at a shorty muffler that terminates just in front of the rear wheel.  And also replacing the lunchbox with BEP 3.0 and a small speedo/gauge.  [size=78%]All the fairings/luggage bits will go away except for perhaps a small front and rear fender.  And I may trim the foot peg brackets some vs. purchasing rear sets.[/size]
  • San Francisco
  • 1990 K75S (in 1000 pieces)

Offline Martin

  • ^ Quintessential Motobricker
  • Posts: 4475
Try looking in http://www.motobrick.com/index.php?board=38.0 for inspiration.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Laitch

  • Faster than a speeding pullet
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  • Posts: 11299
I tried a search and came across some of the more involved options.  But didn't see anything using the existing FI system.  I'll try some more search terms.
That's a good idea. While you're trying to think of some, there's this to look at.

http://www.motobrick.com/index.php/topic,9158.msg90179.html#msg90179
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline oneplustwo

  • ^ Motobrick Curious
  • Posts: 109
Ooh, that's awesome!  I assume I can do something similar in terms of how he fabricated the tubes for the throttle bodies with an adapter to mount the MAF and air filter?


It's actually very close to what I was envisioning for my build.  I might try to maintain the rear seat though.
  • San Francisco
  • 1990 K75S (in 1000 pieces)

Offline Laitch

  • Faster than a speeding pullet
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I assume I can do something similar in terms of how he fabricated the tubes for the throttle bodies with an adapter to mount the MAF and air filter?
You have free will to assume anything.  :yes
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline oneplustwo

  • ^ Motobrick Curious
  • Posts: 109
Indeed.  I've been looking for photos of the K75 intake setup but haven't found much of the assembly.  Will have to wait until I get it apart I guess!



  • San Francisco
  • 1990 K75S (in 1000 pieces)

Offline Laitch

  • Faster than a speeding pullet
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Re: What's the most stripped down K bike you've seen (that still works)
« Reply #10 on: May 03, 2018, 12:34:35 AM »
Indeed.  I've been looking for photos of the K75 intake setup but haven't found much of the assembly.  Will have to wait until I get it apart I guess!
Indeed, unless you have some manuals to consult. Not much difference between the 2V models in that regard except the number of cylinders being fed—2V meaning 2 valves per cylinder.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline duckytran

  • ^ Proficient Motobricker
  • Posts: 211
Re: What's the most stripped down K bike you've seen (that still works)
« Reply #11 on: May 03, 2018, 09:26:15 AM »
Check out Mike Flores' build. He has some nice pics on making the "groove" in the rear seat hoop for the LED light strip.


http://www.motobrick.com/index.php/topic,8807.0.html
  • Austin, Texas
  • 1993 K75, 1981 R65

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