Author Topic: 87 K75C, Bone Stock and DONE.  (Read 211539 times)

Offline The Mighty Gryphon

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #175 on: January 15, 2017, 10:32:34 AM »
Sounds like the clutch friction disc is out of alignment.  What did you use to center it? 

I think you need to pull the transmission and recenter everything.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #176 on: January 15, 2017, 10:52:10 AM »
Phew just got it.  I shifted it into gear gave the output shaft a small turn...aligning the input.  on it slipped right into place.  Wow.
  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #177 on: January 15, 2017, 10:55:49 AM »
Thanks TMG for your quick response!  As soon as the splines lined up it just slipped into place...smooth and easy.
Thats a pretty tight tolerance in there.  HA
  • Illinois
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Offline The Mighty Gryphon

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #178 on: January 15, 2017, 11:08:33 AM »
Congratulations on successfully navigating the worst regular maintenance operation you will encounter on a brick.  :2thumbup:
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #179 on: January 15, 2017, 11:15:13 AM »
Congratulations on successfully navigating the worst regular maintenance operation you will encounter on a brick.  :2thumbup:


LOL THANKS!  and thank god.  If there is anything worse than that...this thing is getting lit ablaze and pushed off a cliff.  HA!!!!
  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #180 on: January 15, 2017, 11:56:19 AM »
Ok just to catch up.  The reason I started all this...
New gear selction switch.  Heavily coated w plastidip installed.  Also, gave the gasket a coat of silicone that never cures...Time will tell.





Now clean up everything that came off and bolt her back together to check throttle body sync.


Oh and fresh valve stems going in wheels.
  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #181 on: January 15, 2017, 02:26:50 PM »
We got grease.


  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #182 on: January 15, 2017, 09:22:59 PM »






Need to quit for today.  Wife has our Anniversary diner ready.
  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #183 on: January 16, 2017, 08:13:38 AM »
Funny how things can go.
Spent 2 hours psyching myself up for "The Dreaded Swinger Boot Installation.  I just knew this was going to be a terror.


So, procrastinated by cleaning up and installing coils.





Then, no choice, ugh, cleaning up the swinger.





Got set up, gave it a couple half hearted wiggles and twists...and "THUMP!"  It popped on. 
I pulled and twisted and pulled like 50 times...it tugged back every time.  THANK GOODNESS!


  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C/T "Flaky Neutral Switch"
« Reply #184 on: January 23, 2017, 06:40:36 PM »

Got the fresh stems installed in the wheels.  I dont have any idea what I was (or wasn't) thinking, not doing them when installing new tires a few months ago.  Is what it is, all good now.





fresh header washers went in.





Cleaning as she slowly comes back together.





The wife helped me carry and load plastics into the dishwasher.  Had to remove the top rack to fit the tail in.








Once done she said "this will be the last time I put motorcycle parts in her dishwasher/oven."  What up w that attitude?


Spot free complements of Cascade w sheeting action!  Ready for an acetone wipe down then strip/sanding for paint.


  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C "A surprise in my mailbox"
« Reply #185 on: February 15, 2017, 07:20:53 PM »

My buddy and his wife flew to Cuba last week to celebrate her birthday.


And all I got is a bunch of lousy Romeo y Julietas, Montecristo and Cohibas. 


The reason the Cohibas arent wrapped, they came directly from the farmer.

















  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C Prepping for paint
« Reply #186 on: February 19, 2017, 05:30:59 AM »




  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C Help needed hunting 2v drop.
« Reply #187 on: February 23, 2017, 06:15:03 PM »
Ive run into a voltage drop issue.  Tank is off bike so fuel pump and sending unit unplugged.

Battery is new and fully charged.  Odyssey 680.

My starter relay picks just fine w the clutch.  12.5v

It does not pic w the neutral circuit.  Dropping 2v somewhere.  Only getting 10.5 to the starter relay coil.

Ive got 12.5v up to and in the instrument cluster.

Gear pcb feeding new gear switch 11.5v to ground on all three leads at the switch connector. 

The gear display and neutral light both working fine.  Opened up the cluster, cleaned the pin connections to the gear selector pcb.

checked the ribbon cable and diode. 














Reading 1.998 meg on diode, not sure what it should be?

Any help you can offer would be appreciated.


I also unplugged the load shed, fuel injection relays and the 12pin connector at the cluster not associated w the gear selector pcb.
  • Illinois
  • 87 K75C

Offline Laitch

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Re: 87 K75C Help needed hunting 2v drop.
« Reply #188 on: February 24, 2017, 10:52:42 AM »
It does not pic w the neutral circuit.  Dropping 2v somewhere.  Only getting 10.5 to the starter relay coil. Ive got 12.5v up to and in the instrument cluster.
You've probably tracked down the problem by now, but maybe it's in the wire connecting the cluster to the right handlebar combo switch connector or within the connection's components.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline Jonico

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Re: 87 K75C Help needed hunting 2v drop.
« Reply #189 on: February 24, 2017, 02:34:57 PM »
Just wanted to say Hi Eric, you've got a great thread going here. I'm U of I alumnus myself, (I wish I had a bike back in those days!). I'm also choking on my own bile that you could get your flying brick for $1000.  Mine here in Spain cost me $2500 and that was a steal. I don't wanna pry, but how much are the repairs running? And what has been the biggest expense so far?
Cheers from Madrid, amigos!
-John


Sent from my iPhone using Tapatalk
  • Madrid, Spain, Europe, Earth and Beyond!
  • 1986 K75RT with ABS (i.e., a K75F)
Living deliberately.

Offline Laitch

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Re: 87 K75C Help needed hunting 2v drop.
« Reply #190 on: February 24, 2017, 02:44:12 PM »
I'm also choking on my own bile that you could get your flying brick for $1000. 
Better than choking on somebody else's. Look on the bright side, Jónico.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline Jonico

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Re: 87 K75C Help needed hunting 2v drop.
« Reply #191 on: February 24, 2017, 03:06:15 PM »
Very true, Laitch, very true.  Is the gallbladder half empty or half full? It's all a matter of perspective! :giggles
  • Madrid, Spain, Europe, Earth and Beyond!
  • 1986 K75RT with ABS (i.e., a K75F)
Living deliberately.

Offline trek97

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Re: 87 K75C Help needed hunting 2v drop.
« Reply #192 on: February 25, 2017, 04:45:25 AM »
You've probably tracked down the problem by now, but maybe it's in the wire connecting the cluster to the right handlebar combo switch connector or within the connection's components.


Thanks Laitch, Its looking like the issue must be one of the components in the gear selection board.  Currently working w rbm to figure it out.  So long as his patience w me holds out.


Just wanted to say Hi Eric, you've got a great thread going here. I'm U of I alumnus myself, (I wish I had a bike back in those days!). I'm also choking on my own bile that you could get your flying brick for $1000.  Mine here in Spain cost me $2500 and that was a steal. I don't wanna pry, but how much are the repairs running? And what has been the biggest expense so far? Cheers from Madrid, amigos! -John


Thanks John,  Single biggest expense so far has been the Major/minor service kits from Bobsbmw.com.  But they sure made it pretty easy to get things rolling.  Its all the little rubber parts, really adding up.  Replacing as I go.   The biggest concern is availability, Theres a few parts, no longer available from bmw.  I would like to replace but just cant find em. 
  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C "Proper" pump re-re-build 2.0
« Reply #193 on: February 25, 2017, 07:22:22 AM »
After rebuilding the pump I found out the old cast impeller cant be used w the new seal. 

Also, after the first rebuild.  The pump wasnt leaking but I didnt feel very confident about using sockets and a hammer to pound the seal onto the shaft.  (youtube "DIY" vids)  So asked my buddy to make me a proper installation tool.

So rebuild 2.0.

Upon disassembly I tore the seal apart to see how it was made.
As suspected I Found it is a VERY fragile thing.  Its made up of 9 separate components.  A ring inside actually appears to be nothing more than a brittle, soft compressed graphite like material.  Its soft enough that I can write with it like a pencil.  And crack it to pieces w my fingers. 
Probably easily damaged under percussive shock of using a hammer to beat it onto the shaft.








Installation tool.  The OD of 34mm is bare minimum.  It can be up to 40mm OD.













I lubed up the oil seal and shaft w 90w and installed them. 

Then thoroughly cleaned and dried the shaft w acetone.  So the coolant seal wouldnt be prone to spinning on the shaft once fitted.




Rather than pounding the thing w a hammer.  Or, fumble farting around trying to turn it onto the shaft using the bolt.


I used a C-clamp to gently press the seal onto shaft and into housing at the same time.



This method worked out GREAT.  I am really confident about the job.




Filled the small space between the seal and shaft w Permatex water pump sealer.





Torqued to 33nm and ready to go on the bike.





Dont know if its for the best.  Maybe threebond would be better.  But, Using Ultra black to seal oil pump/engine surfaces and waterpump sealer on the cover side.

  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C GSB and ICU gone bad.
« Reply #194 on: March 09, 2017, 06:59:06 PM »
RBM saved me!  Thanks to his patience and willing to share knowledge.  He hung in w me.


Replaced the Gear Selector board and Ignition control unit along w a new stock starter relay.





  • Illinois
  • 87 K75C

Offline Laitch

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Re: 87 K75C GSB and ICU gone bad.
« Reply #195 on: March 09, 2017, 07:30:31 PM »
Thanks for the update. Any understanding why the gear selector board gave up the ghost?
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline trek97

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Re: 87 K75C GSB and ICU gone bad.
« Reply #196 on: March 09, 2017, 08:31:15 PM »
Thanks for the update. Any understanding why the gear selector board gave up the ghost?


rbm believes both issues were EMF caused by the collapsing field from the unprotected Trombetta starter relay I had installed.


Who am I to argue w that?  ha.  Im just a relay logic guy...not the solid state sort.

  • Illinois
  • 87 K75C

Offline trek97

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Re: 87 K75C GSB and ICU gone bad.
« Reply #197 on: March 10, 2017, 05:18:51 AM »
Oh, and thanks goes to frankenduck and kbikeparts.com for coming through w the working Gear selector board!   :2thumbup:
  • Illinois
  • 87 K75C

Offline trek97

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87 K75C throttle sw and choke.
« Reply #198 on: March 11, 2017, 10:34:54 AM »
Hey guys I was tinkering and noticed the Throttle position sw wasnt adjusted to "click" when closed.


After adjusting, I noticed it also clicks w stage 2 choke.  But have read nothing about this.


Would anyone mind confirming this result for me.


The choke is adjusted as close to spec as I can kinda sorta best measure it.  stage 1 = 1.5mm, stage 2=3.5mm
  • Illinois
  • 87 K75C

Offline The Mighty Gryphon

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Re: 87 K75C throttle sw and choke.
« Reply #199 on: March 11, 2017, 11:47:40 AM »
I can't point to any documentation, but it stands to reason that the Throttle Position Switch will be activated with the "choke".  THe switch is supposed to be activated at the point where the throttle is just opening.  Since the "choke" is actually opening the throttle a small measured amount it makes sense that it would activate the switch. 

Your question brings to mind two additional questions:

First, should the first "choke" position activate the Throttle Position Switch?

Second, Can the "choke" be used to test the throttle position switch setting rather than the twist grip with all it's free play?  Seems like a better way.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

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