Author Topic: ***FINISHED***: Father & Son 1988 K75S Rebuild  (Read 26170 times)

Offline jay1622

  • ^ Proficient Motobricker
  • Posts: 279
***FINISHED***: Father & Son 1988 K75S Rebuild
« on: August 03, 2015, 02:22:00 PM »
Good afternoon everyone. I am hoping to pick your brains and get some thoughts and/or advice as to what you think I am seeing and what some of the causes/remedies may be.

I managed to get a little bit deeper into the bike yesterday and stumbled onto a few things that I will want to address. When I took off the lower faring, both the front and the rear of the engine had significant dirt residue. There is no smell to it so I could not figure out if it is gear oil, coolant, or oil. I'm ruling out fork oil for now due to the fact that the seals appear to be in great condition, the fork tubes look great, and there wasn't any residue on the front of the fairings.  My initial guess is I have a coolant leak upfront and a gear oil leak in the back. I hope that's not the case, but considering where the paint has come off and how, that's what I'm thinking so far. Thoughts?  Recommendations? Clutch nut perhaps?

Worst case scenario, I will just replace the seal of whatever leaks I may find as I go; just hoping it's nothing significant when I get there.

Around the electrical wiring harnesses, it looks more like friction tape, as opposed to electrical tape. Does anybody know if this is true?

For the splines, I have and have been using the Honda Moly 60 for the splines on my RT. I will assume I can clean off the old crud and use the Molly 60 in its place? I've seen in places that I can, but I wanted to hear it from you guys whether or not there is a better option out there.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline jay1622

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  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #1 on: August 03, 2015, 07:30:29 PM »
Also...

Is there any way to tell if I have the 12mm or the 13mm rear brake master cylinder? Yes, I know measure... But where? Are they universal?
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline Chaos

  • ^ Quintessential Motobricker
  • Posts: 2205
  • Mars needs women!
Re: Father & Son 1988 K75S Rebuild
« Reply #2 on: August 03, 2015, 09:20:56 PM »
Also...

Is there any way to tell if I have the 12mm or the 13mm rear brake master cylinder? Yes, I know measure... But where? Are they universal?

13mm for non-abs up to oct,1988, 12 mm for abs bikes and non abs 10/88 and later
  • sw ohio
1987 K75S    VIN 0231
Original owner, Original litter
200,000 miles (plus or minus) and 5 paint jobs
2012 Ural 2WD sidecar (BMW's bastard step child)

Offline K75RT Keith

  • ^ SuperNatural Motobricker
  • Posts: 437
Re: Father & Son 1988 K75S Rebuild
« Reply #3 on: August 04, 2015, 11:07:40 AM »
"Around the electrical wiring harnesses, it looks more like friction tape, as opposed to electrical tape. Does anybody know if this is true?"  Yes they used what appears to be friction tape. 

"For the splines, I have and have been using the Honda Moly 60 for the splines on my RT. I will assume I can clean off the old crud and use the Molly 60 in its place? I've seen in places that I can, but I wanted to hear it from you guys whether or not there is a better option out there."    Honda Moly60 is fine.
* * * * Be aware that Honda is discontinuing Moly 60 * * * . So get it while you can find it. 

Guard Dog makes a high moly lube and a paste.  The paste can be mixed in to a lower moly based lube if needed.
You can't help someone who doesn't want to hear the answer.

1990 K75RT

Offline jay1622

  • ^ Proficient Motobricker
  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #4 on: August 22, 2015, 06:26:16 PM »
Hey all, I was conducting an inventory of what I have so far, and I figured it was worth sharing the pic. Am I missing anything?

Oh, and huge props to the parts department at Motorcycles of Charlotte. They worked with me more than I could have imagined and were very patient at helping me sort all of the stuff; and this still is not all of it.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline K75RT Keith

  • ^ SuperNatural Motobricker
  • Posts: 437
Re: Father & Son 1988 K75S Rebuild
« Reply #5 on: August 22, 2015, 07:37:47 PM »
Looks like you emptied the trust fund.   Only way you'll know if you got all the parts you need is to commence wrenching.
You can't help someone who doesn't want to hear the answer.

1990 K75RT

Offline Chaos

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  • Posts: 2205
  • Mars needs women!
Re: Father & Son 1988 K75S Rebuild
« Reply #6 on: August 22, 2015, 08:09:05 PM »
Hey all, I was conducting an inventory of what I have so far, and I figured it was worth sharing the pic. Am I missing anything?



don't forget to lube the barrel that holds the clutch cable to the hand lever.  I haven't bought that many BMW labeled plastic bags in the 28 years I've owned mine!
  • sw ohio
1987 K75S    VIN 0231
Original owner, Original litter
200,000 miles (plus or minus) and 5 paint jobs
2012 Ural 2WD sidecar (BMW's bastard step child)

Offline jay1622

  • ^ Proficient Motobricker
  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #7 on: August 22, 2015, 08:25:14 PM »
Thanks guys! Without sounding too much like a pitch man for the local dealership, the guys in parts really did me one solid. I hear what you're saying about the clutch cable. I have seen that time and time again in my old Yamaha Enduro bikes from the 80s. As for having all of the parts I will need? Time will tell, but I am pretty sure that this should be it with the exception of a few things. Namely, the final drive service plate I will have to fabricate to replace the seal and the clutch isolater I'll be making.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline RobP

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  • Posts: 143
Re: Father & Son 1988 K75S Rebuild
« Reply #8 on: August 24, 2015, 08:21:18 AM »
Quote
As for having all of the parts I will need?

What I do appreciate is that BMW will still supply parts for these bikes that are ~30 years old, at somewhat reasonable prices.   Can't say that for other brands.
  • Driftwood, TX
  • 1985 K100RS

Offline jay1622

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  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #9 on: December 30, 2015, 10:10:14 PM »
Some updated Pics... Coming along quite nicely, or, so I hope!
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline F14CRAZY

  • ^ Quintessential Motobricker
  • Posts: 1091
Re: Father & Son 1988 K75S Rebuild
« Reply #10 on: December 31, 2015, 06:17:34 AM »
Quote
As for having all of the parts I will need?

What I do appreciate is that BMW will still supply parts for these bikes that are ~30 years old, at somewhat reasonable prices.   Can't say that for other brands.

I wouldn't quite call BMW parts cheap but I haven't felt like I've been completely ripped off by them (yet). Nice they have things like clutch cables and discs in stock
  • Grand Rapids, MI
  • '87 K75C
'87 K75C w/ Pichler V1 fairing. LED's, CATZ driving lights, Audiovox cruise, LT top case, tons of other mods by Drake...


Offline The Mighty Gryphon

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  • Posts: 3920
Re: Father & Son 1988 K75S Rebuild
« Reply #11 on: December 31, 2015, 10:23:40 AM »
Thanks for the photos.  If your engine work is even half as good as the photos, that bike will be a real beauty.
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '92K100RS White, '94 K75S Dakar Yellow
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'94 K75S "Cheetos"
'91 K100RS "Moby Brick Too

Offline 67charger

  • Motobrick Curious
  • Posts: 32
Re: Father & Son 1988 K75S Rebuild
« Reply #12 on: January 02, 2016, 06:30:44 AM »
After seeing pictures of that head, It seems HEMI badges would be appropriate.
  • pennsylvania
  • 1993 k75

Offline Martin

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  • Posts: 3487
Re: Father & Son 1988 K75S Rebuild
« Reply #13 on: January 02, 2016, 02:01:49 PM »
I've always wanted to own a Hemi I didn't realise that I've owned one for the last 17 years. :clap:
WooHoo Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Scud

  • ^ Proficient Motobricker
  • Posts: 364
Re: Father & Son 1988 K75S Rebuild
« Reply #14 on: January 02, 2016, 07:01:47 PM »
Holy smokes - this is more like a restoration than a rebuild. FANTASTIC.
  • Carlsbad, CA
  • 1992 K75s. 2002 Moto Guzzi V11 Scura, 2003 Moto Guzzi V11 LeMans. 2007 Husqvarna TE450

Offline jay1622

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  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #15 on: February 21, 2016, 11:22:51 AM »
New clutch pack went in last night. He continues to help and show interest.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline jay1622

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  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #16 on: February 23, 2016, 04:15:11 PM »
Mostly organized the garage (and my mind) today more than anything else, but I did manage to get a few things sorted. Got the rear suspension figured out, and the oil/water pump rebuilt and installed, and the air filter boxes sorted and ready for install as soon as I get some replacement fuel hose.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline sj2000

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Re: Father & Son 1988 K75S Rebuild
« Reply #17 on: March 11, 2016, 02:44:49 PM »
WOW, two thumbs up! :2thumbup:
  • Parker, USA
  • 1985 K100

Offline Quiltzig

  • ^ Motobrick Curious
  • Posts: 86
  • K Guy
Re: Father & Son 1988 K75S Rebuild
« Reply #18 on: July 12, 2016, 05:38:58 AM »
Any progress to report since February?

I was enjoying following your restoration project.
  • Hamilton - New Zealand
  • K75S x2
1987 K75S - cafe racer project
2016 R9T (wifes ride)
1998 K1200RS
2004 K1200RS

Offline jay1622

  • ^ Proficient Motobricker
  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #19 on: July 12, 2016, 09:02:56 AM »
Tons of progress... Thanks for asking. ALL mechanical issues have been addressed and everything is back together. Fairings have been test-fit. Here's some progress related pics... Look to have her finished within the next few weeks.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline jay1622

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  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #20 on: July 12, 2016, 09:05:14 AM »
As of last week...
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

Offline Martin

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Re: Father & Son 1988 K75S Rebuild
« Reply #21 on: July 12, 2016, 11:17:08 AM »
 :2thumbup:Looking good I could never get any of my kids interested in anything mechanical.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Quiltzig

  • ^ Motobrick Curious
  • Posts: 86
  • K Guy
Re: Father & Son 1988 K75S Rebuild
« Reply #22 on: July 13, 2016, 06:11:47 AM »
Thanks for the update. I only have daughters, and a grandson who is a whizz with computers but brings his motorbike to me to fix all the time. Glad to see the father / son bonding Taking place !
  • Hamilton - New Zealand
  • K75S x2
1987 K75S - cafe racer project
2016 R9T (wifes ride)
1998 K1200RS
2004 K1200RS

Offline The Dude

  • ^ SuperNatural Motobricker
  • Posts: 509
Re: Father & Son 1988 K75S Rebuild
« Reply #23 on: July 17, 2016, 12:45:58 AM »
You've created an hair loom...
Nice.
  • Auckland, New Zealand
  • K75s
Current.
TR6R 1973 from new.
Moto guzzi 850 III .1983 from,almost, new.
K75S 1986 from new.vin-0103141
On my second millionth km.give or take a hundred k Kay's.
"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there."
All the best!

Offline jay1622

  • ^ Proficient Motobricker
  • Posts: 279
Re: Father & Son 1988 K75S Rebuild
« Reply #24 on: August 04, 2016, 10:46:12 AM »
Started the final phase of the rebuild. The panels were cleaned with hot soapy water. Next will be stripping, scuffing and repairing what's broken.
  • Charlotte
  • Previous: 1986 K75S, 1977 R75/7, 1999 R1200C, 2003 R1150GS, 2001 F650GS, 2005 R1200RT... Current: 2005 R1200RT and my Brick, a 1988 K75S

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