Author Topic: Getting my '93 K1100RS Roadworthy.......Again.  (Read 816 times)

Offline Big_B

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Getting my '93 K1100RS Roadworthy.......Again.
« on: May 26, 2019, 04:32:41 PM »


Let me start by thanking the members here for helping me over the years. The wealth of knowledge shared has been a deciding factor in keeping me interested in the K Bikes. Thank you guys, truly priceless.

Having lost my storage, I'm in the process of getting my K1100RS with 75K miles ready for the road, and possibly offering for sale after it's done. It's a long story, I'll try to keep it somewhat brief.

A little history on it: Purchased back in 2009. She needed a battery, fuel pump, cooling fan and tires, but was beautiful to me. She ran great once I installed a Ford fuel pump, aftermarket cooling fan and Michelin tires. Move on to the dreaded driveshaft failure and that's how I linked up with Duncans Beemers in Maynard Ma. They provided me with a low mile shaft that has performed flawlessly. Somewhere in the 30K miles I put on her, the key was lost. A locksmith worked on it for 5 hours and could get into the tank, under seat lock, but not the ignition. At that time, the bike was my only mode of transportation and I needed it running ASAP so I allowed him to drill it out. The bike ran great until a green wire decided to no longer be soldered to the ignition wire harness. At that point I had to store it in my grandmother's shed.

She has since passed away and the bike had been there for 6 years, now I'm left with a decision to make. I can't bring myself to dismantle this beautiful bike, but it does need some work and I don't have permanent storage.

Here's a list of what I know it needs:

Battery
Fork seals leak
Final drive needle bearings/ very little play, but not worth neglecting
Cooling fan bearing stuck
Fuel cap replace gasket
Corbin seat worn/torn needs recovering


My primary focus now is to get her running before diving into the forks, fan, seat and needle bearings. I know I tend to have tunnel vision and can't afford a couple thousand dollars of parts, so I'm trying to keep costs down.

Progress so far:

I'm almost done with removing the top triple clamp/soldering the green wire, head bearings feel good.  The tank is full of old gas. I'll pull the fuel and look to see how bad it is in there soon. Hopefully there won't be too much gunk from the ethanol sitting? Wishful thinking. I'm 99.9% confident it'll start with a new battery and decent fuel.

I'll keep posting the progress made good or bad.








  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Online Laitch

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #1 on: May 26, 2019, 05:51:21 PM »
Thanks for the pics. Good luck with the rehabilitation!
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline volador

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #2 on: May 27, 2019, 05:41:45 PM »
If your OEM fan doesn't cooperate any longer you may consider upgrading to a Spal Fan
  • NYC
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY "When Life Throws You A Curve... Lean Into It"

Offline Big_B

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #3 on: May 28, 2019, 12:47:22 AM »
If your OEM fan doesn't cooperate any longer you may consider upgrading to a Spal Fan


Yes I'll be replacing the fan. The Spal fan does look like a great replacement. But the generic 12 volt brushless fan, I installed years ago, got me 30k miles and was dirt cheap.


Progress Done Today

Today was a good day working on the bike. I managed to remove the upper triple clamp. I needed the clamp off to install the new clamp with working factory key. Turned out I just needed to put a little more effort into prying it off the stem. Once the clamp was off I spotted a loose green wire on the back of the ignition plug. Out comes the soldering iron for the loose green wire and to reflow the remaining connections. It's been so long since I've seen this bike have a key! :)

Next I got the fuel cap off the tank. The shallow depth on some of the oem hardware does make it easy to strip. Good thing I used anti-seize on them when I did the Ford fuel pump conversion or they would've stripped for sure. After the cap came off I was relieved to not see the massive amount of gunk that was there when I got the bike. Just some old gas with a little water on the bottom, I'll be replacing the gasket too.

I'm very hopeful that it'll start once the new battery is installed along with fresh fuel. Then it's on to the fork seals, seat and final drive bearings.

  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Offline Big_B

  • ^ Motobrick Curious
  • Posts: 76
Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #4 on: June 02, 2019, 01:23:57 AM »
It's all coming back to me now!

It's been a little while since my last update. Finally got the tank drained, took out the old filter and inspected the pump. Determined that the generic E2042 pump needed to be replaced. (rust hole in the case). No biggie I ordered a new fuel pump, filter, oil filter and wrench. Great well on my way to hearing her run again!

I woke up today excited, see the mailman and grab my parts. Head out to the garage and install the pump and filter, check. Plug in the ECU and other box thing, check. Carefully hook up the fully charged battery, check. Place the key in the ignition and turn it, whole lot of nothing.....GRRRRRR. I did notice the clock works, awesome.

It all comes back to me now, the bike started cutting out on me randomly. This loss of power and leaking fork seals, along with life's issues, cause me to park it until recently. Now that I've fixed the disconnected green wire(on the back of the ignition), I thought that was def my no power issue, but couldn't be more wrong. I do hear the LSR clicking while turning the key, but no fuel pump prime or dash lights.

Obviously I'll be checking all the grounds and getting very friendly with my multimeter tomorrow. But geesh I'd like to have a more positive feeling that I'll figure it out. I'm having flashbacks of putting my starter together backwards and wondering why she won't start again.

It's all coming back to me now!
  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Offline volador

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #5 on: June 02, 2019, 01:31:44 AM »
1. Check fuse #1 -Instrument Cluster
Fuse #6- Fuel pump 
Both are  7.5A

2. If you pull the clutch lever in when starting anything?
Two interlocks interact: It should start if it is in neutral; or if the clutch lever is pulled if in gear. There is a gear position indicator switch at the transmission and there is a clutch switch up by the clutch lever.

So, if in gear pulling the clutch should allow it to crank. If not, the clutch switch is suspect.

If the neutral light fails to come on that switch seems faulty. If both get bad it won't start.

3. Is the side stand switch bypassed?

4. Check the 4-Pin connector for the Fuel Level Sender
Manipulate the pins/socket for a solid connection.

How is the condition of the level sender inside the tank?

4 pin configuration on the male end of the Petrol Gauge Level Sender

1.Brown-is ground continuity to the larger diameter ring terminal
2.Green-is 12V continuity to the smaller diameter ring terminal
3.Yellow-is fuel level
4.White-is 4 litre reserve indicator
Remove the ring terminals from the fuel pump to perform continuity test

5. If its a starter issue you may need to clean starter commutator and/or change the starter brushes.

Starter Motor Backspin
Try doing a starter backspin. With the engine off and in 3th or 4th gear roll the bike backwards down a hill and pop the clutch a few times allowing the starter to spin backwards. This procedure normally dislodges the built up carbon from the brushes allowing the bike to start. The more permanent fix is to remove the starter, pull it apart, check the brushes/commutator and clean.

Starter motor cleaning / rebuild tutorial



  • NYC
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY "When Life Throws You A Curve... Lean Into It"

Offline Big_B

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #6 on: June 02, 2019, 03:48:26 AM »
Check fuse #1 -Instrument Cluster

Fuse #6- Fuel pump

Both are  7.5A

Hi Volador,

I checked the fuses, all good. The relays have been pulled and checked for corrosion. Double checked/wiggled the harness connections. Overall the harness looks good, there's no corrosion or chaffing. I had the "key on no power issue" before and fixed it years ago, but I'm fuzzy on exactly how to fix it. If my memory serves me right there's a situation where the starter brushes won't allow current thru?

I'll be open to any words of wisdom and armed with a fresh battery in the multi meter tomorrow.  :bang-head:
  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Offline volador

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #7 on: June 02, 2019, 03:56:54 AM »
The "load shed relay" which has the headlight and some other stuff connected grounds to the hot brush of the starter. If the starter is not energized this provides a path to ground for the relay coil, thus providing current to the headlight, etc.

However, when the starter button is depressed 12v+ is applied to the hot brush. And the load shed relay coil now has 12v+ applied to both ends of the coil - thus no ground. So the relay turns the headlight and stuff off until the starter button is released.

https://forums.bmwmoa.org/showthread.php?94841-1990-K75RT-Electrical-problem
  • NYC
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY "When Life Throws You A Curve... Lean Into It"

Online Laitch

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #8 on: June 02, 2019, 06:56:18 AM »
I'm having flashbacks of putting my starter together backwards and wondering why she won't start again.
It's all coming back to me now!
This thread you started six years ago will flesh out your flashbacks. Please review it and determine what is differing now.
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider

Offline volador

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #9 on: June 02, 2019, 03:05:23 PM »
There is also a frame ground wire connection on the left side of the center frame tube under the gas tank
  • NYC
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY "When Life Throws You A Curve... Lean Into It"

Offline Big_B

  • ^ Motobrick Curious
  • Posts: 76
Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #10 on: June 03, 2019, 02:34:04 PM »
This thread you started six years ago will flesh out your flashbacks. Please review it and determine what is differing now.

Maybe it's early symptoms of Alzheimer's, I forgot all about that thread until I found it a couple nights ago!  :dk  Great resource to have a documented history like Motobrick, I'd be lost without it. It's amazing that the same members are still here helping others.

I forgot that key on no power can be caused from a dirty starter until I reread my original thread. Almost done pulling the starter to clean, guess we'll see if that gives me dash lights. If it doesn't I'll clean the contacts on the ignition switch.

Thank you for your patience, it'll fire soon.

  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Offline Big_B

  • ^ Motobrick Curious
  • Posts: 76
Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #11 on: June 13, 2019, 02:41:26 PM »
The saga continues, I'm running out of ideas of why it won't start.

Cleaned the starter, installed it and have the same issues. I took out my multi-meter and found the relays have power, but only my dash clock is working. There's no fuel pump prime or dash/headlight. The only new clues I have is 0.05 volts on the starter bolt with the key on and a broken wire on what I believe is the gear position indicator connector.

Am I correct in suspecting a faulty kill switch?
Am I correct with that the broken wire is my gear position indicator or something else?


I really expected to have it running by now and running out of options/ideas.  :computer-noworky:
  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Offline volador

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #12 on: June 13, 2019, 09:01:54 PM »
The connector shown is for the sidestand switch.

You can use contact ring part number 61121459998 or whatever means necessary to bypass the switch.

http://www.motobrick.com/index.php/topic,574.msg1507.html#msg1507

The Bypass Connector


* SideStandSW.jpg (60.29 kB . 764x576 - viewed 55 times)


When starting, the starter will engage, fuel pump and headlight will work even thou sidestand switch is inop.
In practice the engine will turn over but will not start until the side stand is raised.

1. No key required. Take voltmeter +POS lead to the battery POS terminal

Voltmeter -NEG lead to Starter terminal post should read battery voltage. No reading - Starter issue open ground


2. The following will require Ignition Key but Do Not Push The Starter Button

Take a decent jumper wire connect to the Starter terminal post the other end to ground

Turn Ignition Switch On: if headlight and instrument cluster work - Starter issue open ground- remove jumper


3. If when doing #2 the headlight and instrument cluster did not work- possible Load Shed Relay issue

Switch Load Shed Relay with the Horn relay

When starting pull Clutch lever in until you've solved the problem
  • NYC
  • 1991 K100RS 1993 K75S ABS
5 BOROUGHS SISYPHEAN SOCIETY "When Life Throws You A Curve... Lean Into It"

Online Laitch

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Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #13 on: June 14, 2019, 12:53:21 AM »
If it doesn't I'll clean the contacts on the ignition switch.
It didn't, so did you? Also clean the ignition switch connector at the wiring harness.
  • Along the Ridley in Vermont.
  • 1995 K75 72,000 miles
I wept because I had no radials until I met a man who had no splines.
https://tinyurl.com/RillRider
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Offline Big_B

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  • Posts: 76
Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #14 on: June 14, 2019, 03:14:25 PM »
Heading out to the garage. I'll clean the ignition switch and take care of the side stand switch broken wire issue.

Thank you for keeping me on track guys, I appreciate it.
  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

Offline Big_B

  • ^ Motobrick Curious
  • Posts: 76
Re: Getting my '93 K1100RS Roadworthy.......Again.
« Reply #15 on: June 14, 2019, 05:59:59 PM »
It didn't, so did you? Also clean the ignition switch connector at the wiring harness.


Laitch for the win! I now have power to my dash & headlight.

I'll take a video of it firing up once I get it together. She's in a million pieces as she sits.
  • North Easton, MA
  • 93 K1100RS
'93 K1100RS 75K miles all stock w/Fox aftermarket shock Corbin seat.

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