Instagram     

Go Back   PNW Moto > PNW Moto > Mechanical and Technical

Mechanical and Technical Mechanical and technical topics, help, and discussions

Like Tree22Likes
Reply
 
Thread Tools
Mar 4th 2017, 08:04 PM   #1
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

'87 BMW K100 Project

So my garage was without a project last spring and I came across a great deal on two '87 BMW K100's. One with a blown engine but clean title one with a good engine and salvage title. I've always loved the K series "bricks" so i thought i would start another project.

Here are the two bikes as i brought them home.


bcj likes this.
Mar 4th 2017, 08:23 PM   #2
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

The first job was taking all the plastics off and swapping the frame and engine to get the good engine on the clean title frame. For the most part it was pretty easy. there are literally 6 bolts that hold the frame to the engine so you can just put a jack under the engine, pull the bolts and wheel it off on the front wheel roll the second frame over set it down and reinstall the bolts. The hardest part was un-cliping wires and getting them all back routed and connected.





After swapping the frame i put some straight handlebars on it and so i needed to shorten the cables. Since i was going to be tearing into the controls i decided to rewire in some more modern and smaller controls off of a Kawasaki to clean things up and get rid of the old worn out connections. In order to solder up the new ends on the cables i created a little mini melting pot to dip the new ends in and solder up. It worked surprisingly well!



New throttle tube and pull



New Left hand controls from an '02 ZZR 1200 successfully spliced into the wiring after a lot of trial and error, but finally got it to work like its supposed to!


Right hand controls from a ZX10

Edited by revrdmark on Mar 4th 2017 at 08:27 PM
Mar 4th 2017, 08:47 PM   #3
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

Every Cafe Racer gains 10 hp and 15 mph by puting gaiters on the front forks :-)



In general the wiring and instruments on these old BMW's is incredibly complex and totally over engineered. I wanted to get rid of that HUGE 80's instrument cluster and replace it with a much smaller simpler one. The way the speedo drive works from the rear wheel makes it basically incompatible with any other instrument cluster w/o creating a new wiring board curcuit. So i abandoned that system and put in a very simple Acewell computer on it with a Speedo, Tach Fuel Gauge, and Odometer. The speedo is a simple magnet and sender on the front wheel. The tach runs off of the #1 spark plug wire, and i had to reverse the wires on the fuel float so that it would work with the Acewell gauge. I made a simple mounting bracket with some Ebay LED lights to give me a neutral light, an oil light and two turn signal lights. In order to get the Neutral light to work I had to create a series of relays to open the correct circuit and fire the light. Luckily i found a diagram and was able to make it work.

Rough form for the bracket for gauges:


Mostly complete gauge setup:


Fabricated Speedo Sensor bracket:


Fabricated and relocated a spot for the key switch (it needs a coat of paint) Made it out of plastic from a cutting board i bought at Goodwill for $1
Mar 4th 2017, 09:04 PM   #4
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

So i kinda suck at welding but have been practicing and although the welds are not pretty and i still usually need to clean them up after they seem to be strong enough to hold two pieces of tubing together with good strength.

With fear and trepidation i decided to tackle cutting the tail of the frame, welding in an end piece, and angling up the tail to match the angle of the new seat pan. after i got the tail welded up i used more of my $1 cutting board to make a platform for the BMW ECU to be mounted to.


Next i went to the local hardware store and got some square tubing to fabricate a mounting spot for the new seat pan to connect to. Again it wasn't pretty but a grinder and black paint cover a multitude of sins :-)
Mar 4th 2017, 09:21 PM   #5
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

So i was kind of going for a Ducati GT100 Sport classic look so I purchased a little bullet fairing from china and fabricated a bracket to hold it on, and bought a Ducati GT100 tail piece from and fastened them on. I'm liking the look of it so far. I have a few wiring projects still to do to fabricate brackets for the turn signals and brake lights. Still need to attach a Supertrapp exhaust i purchased of Ebay





So since the weather has been so cold my garage has been freezing so the project is kind of on hold. I'll post more as i progress on the project
307T and DaveS like this.
Mar 5th 2017, 04:18 AM   #6
 galenernest's Avatar
 
  Jan 2016
  Beijing

  Honda CBF190R
Very cool project, Mark! Keep the updates and photos coming. I love the industrial gauge cluster and dummy lights
Mar 5th 2017, 08:26 AM   #7
bcj
 bcj's Avatar
 
  Jan 2016
  teh rock

  K1200RS SV650
Are the fuel line connectors to the tank plastic or metal?
The plastic ones on K12 motors were a known liability.
I changed mine for metal quick disconnects from pirates lair.
Mar 5th 2017, 03:22 PM   #8
 ZXtasy's Avatar
 
  Jan 2016
  Moses Lake, WA

  2013 Kawasaki Concours C-14, 2005 ZX-10R Kawasaki (Nekkid), '99 Yamaha TW-200
Love where you are going with this!
Mar 5th 2017, 05:04 PM   #9
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

The fuel tank is aluminum, pressurized and has an in tank fuel pump, so swapping it out for another style or kind makes it pretty impractical w/o major work to the tank to make it function correctly. The K100's have all metal tubes for the fuel tank so I have to really screw up to snap or break them off :-)


Sent via iPhone
bcj likes this.

Edited by revrdmark on Mar 5th 2017 at 07:53 PM
Apr 2nd 2017, 11:23 PM   #10
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

The tank has been a PITA to strip. I've used Citri-strip on projects in the past but this tank has been repainted 4 times so the stripper took forever to get the job done. I put the final touches on wiring and put the super trapp exhaust on. It's starting to look like a motorcycle!






Sent via iPhone
PeteN95 likes this.
Apr 3rd 2017, 01:16 AM   #11
 307T's Avatar
 
  Jan 2016
  Washington County

  H-D
I really admire the patience and skills some people have. Nice job Mark. Look forward to more updates.
Apr 3rd 2017, 08:23 AM   #12
 oldmanriver's Avatar
 
  Jan 2016
  Battle Ground

  1991 Honda CBR1000F
Looking good Mark. I have just enough patience to do what I need to do to ride. Although I did get a few pieces of fairing for the old CBR1000F, sparay paint, and it looks 1000 percent better.
Apr 3rd 2017, 12:18 PM   #13
 ZXtasy's Avatar
 
  Jan 2016
  Moses Lake, WA

  2013 Kawasaki Concours C-14, 2005 ZX-10R Kawasaki (Nekkid), '99 Yamaha TW-200
Looking very cool so far! Am very entertained and inspired to get back going on my 78 GS-550....keep it coming as you can.
revrdmark likes this.
Apr 8th 2017, 08:41 PM   #14
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

Did some more work on the brick today. Finished up filling in a few little dents in the tank with bondo and got the tank and tail primed. Got a base coat of color on the tail. I'll try and get the tank colored tomorrow.








Sent via iPhone
ZXtasy likes this.
Apr 9th 2017, 03:47 PM   #15
 revrdmark's Avatar
 
  Feb 2016
  Spokane, WA

First coat of color on the tank.




Sent via iPhone
ZXtasy likes this.
Reply

  PNW Moto > PNW Moto > Mechanical and Technical

Tags
bmw, k100, project



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale: 2002 Yamaha R1 project jedijesus Classifieds 0 Jan 27th 2017 10:11 PM
ANOTHER 10R trackfighter project... TRAIL BOSS Mechanical and Technical 31 Jun 10th 2016 08:11 AM
Daytona 675 Project 675Rocket Mechanical and Technical 36 Apr 30th 2016 11:58 AM
Cheap Luggage Project revrdmark Mechanical and Technical 6 Mar 31st 2016 04:27 AM




Copyright © 2017 PNW Moto. All rights reserved.