Author Topic: '85 RS Porch Ornament Gets New Home  (Read 12448 times)

Offline Nailhead

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'85 RS Porch Ornament Gets New Home
« on: March 03, 2018, 10:12:36 AM »
As mentioned in my intro thread, I became the lucky beneficiary of a work-for-bike trade in the form of a blue '85 K100RS with 64K-ish miles.  It was last registered in '01.


After considerable thought, I've come up with what I consider a fiscally sensible plan of attack, given how low the values of these bikes seem to be.  First, I'm going to remove the final drive per Chris Harris's colorful guidance, and check the splines.  If they're in good shape, then they'll get buttered with some moly paste, and the rehab will begin.  All rubber hoses will be replaced, a mirror somehow procured (the PO has no idea where the missing one went [insert grumpy smiley here]), and I'll treat myself to the Bosch fuel pump replacement kit I saw offered somewhere online (I realize cheaper alternatives are available, but I intend ride this bike in Wyoming quite a bit, and reliability and peace of mind in such a rural setting is imperative).


If the final drive splines are roached, then some hard choices need to be made in light of other expensive parts (mirror, shock, all those hoses, battery, MC's, etc.) that need to be procured.  The final drive splines will probably be the failure criterion I have to go by.  Here's hoping.


Pix to follow in next post.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #1 on: March 03, 2018, 10:15:14 AM »
The reveal:



Back at our shop with a roof over its head:

More pix will follow as work progresses.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S
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Offline The Mighty Gryphon

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Re: '85 RS Porch Ornament Gets New Home
« Reply #2 on: March 03, 2018, 10:34:50 AM »
$.02 here.  If you are on a tight budget, defer the mirror.  Get a set of LED turn signals and bar mounted mirrors.  The bike will look better(in some eyes but not all), and you can get mirrors and turn signals on eBay for under $30 total.  Then you can ride while you look for another mirror to show up for a reasonable price if you still want one.

Before you go full replace on the rubber bits, disassemble the bike and do a careful inspection of them.  I bought a '91 RS a couple years ago that had sat for several years, and found that the only rubber bits that had perished were the fuel lines. 

Check with the local auto parts store for a fuel pump.  The Ford Mustang is reported to use a similar pump and they can be had for about $60.  Chinese parts are getting better now.  I have an $11 rear master cylinder on my touring bike that has 8,000 miles on it and works better than the OEM unit ever did.  I think Martin has a Chinese pump on his bike and has had good service from it.  The prices are low enough that you can buy two and carry one as a spare(I do that when I'm out West in Montana and Wyoming).

eBay is a good source of used parts as there are a number of bike breakers selling there.  These are large outfits who do a lot of business and sell good quality parts.  You are especially fortunate in that there are at least two that I know of in Colorado that I have bought parts from.  They are close enough that you can save on shipping costs.

Good luck and enjoy the project!
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline The Mighty Gryphon

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Re: '85 RS Porch Ornament Gets New Home
« Reply #3 on: March 03, 2018, 10:53:11 AM »
Further thought on rubber bits.  Rubber bits for BMW bikes are stupid expensive.  Seems to be a lot of competetion for rubber in German industry.  The less you have to buy the more cost effective your rebuild will be.

The big enemy of rubber is Ozone and UV both of which are more plentiful outdoors so if the bike was stored indoors you may not have a lot of damage.  Also, judging from the look of the seat, it appears that the rubber may indeed be in usable shape.   

  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #4 on: March 03, 2018, 11:49:39 AM »
$.02 here.  If you are on a tight budget, defer the mirror.  Get a set of LED turn signals and bar mounted mirrors.  The bike will look better(in some eyes but not all), and you can get mirrors and turn signals on eBay for under $30 total.  Then you can ride while you look for another mirror to show up for a reasonable price if you still want one.

Before you go full replace on the rubber bits, disassemble the bike and do a careful inspection of them.  I bought a '91 RS a couple years ago that had sat for several years, and found that the only rubber bits that had perished were the fuel lines. 

Check with the local auto parts store for a fuel pump.  The Ford Mustang is reported to use a similar pump and they can be had for about $60.  Chinese parts are getting better now.  I have an $11 rear master cylinder on my touring bike that has 8,000 miles on it and works better than the OEM unit ever did.  I think Martin has a Chinese pump on his bike and has had good service from it.  The prices are low enough that you can buy two and carry one as a spare(I do that when I'm out West in Montana and Wyoming).

eBay is a good source of used parts as there are a number of bike breakers selling there.  These are large outfits who do a lot of business and sell good quality parts.  You are especially fortunate in that there are at least two that I know of in Colorado that I have bought parts from.  They are close enough that you can save on shipping costs.

Good luck and enjoy the project!


I love the integrated approach designers of '80's & '90's faired bikes took (hence the R100RS & 900SS in my sig line), and one aspect of this integrated design that I see as crucial to the whole is the design of the turn signals.  I love those of the two above-mentioned bikes, and how they're bespoke, conforming to the lines of the surface in which they're mounted-- much like those of the K100RS.  I hate the way modern designers design a fairing and then just tack on parts-bin turn signals, so I'll be patient.  Good things come to those who don't get in too much of a hurry.


After reading rehab info on at least three forums (fora?), I've come to the conclusion that one should at the very least replace all fuel & vacuum hoses.  There's a good chance the coolant hoses are ok, but my need for peace-of-mind will prevail over thrift when dealing with such critical components (or mirrors...): any doubt, change it out.  Same goes for fork seals: I remember the big oil stain on the driveway after my dad's Rickman blew its fork seals, and that's not something I want to see in a driveway in Wheatland, WY on a Sunday afternoon.


I've read multiple fuel pump threads here and on the K100 forum, and have become aware of several alternative fuel pumps (as I mentioned above), but changing a fuel pump 20 miles south of Chugwater holds no appeal to me, no matter how cheap I bought both pumps. When my old Chevy S10 was rear-ended, I took the opportunity to change out the in-tank fuel pump before we mounted the replacement bed. I bought the factory pump at triple the price of the cheapest alternative, and never regretted the money spent.  It seems the older I get, the more valuable peace-of-mind becomes.


As for eBay, I scrolled through RS parts the other night until I got cross-eyed.  Found some good stuff (a few final drives, an engine spoiler, and some side panels to replace the sloppily repaired left one I have), but no mirrors that weren't beat up from the feet up.  I'll keep looking.


We have a motorcycle salvage yard here in town, but his hours are like caddy day at Bushwood: open for like 15 minutes on Sunday afternoon.  I'm not even sure he opens at all these days. Consequently, I haven't stopped in, even though my Benelli needs several pieces.   Could you pass along the names of those salvage outfits you mention?  It might be worth stopping in.


Thank you very much for your input, and please don't misinterpret my responses as out-of-hand dismissals: I've rehabbed everything from Fiat 500C's to Jeep M715's to Cub Cadets, and maybe have become set in my ways.  I do appreciate the input, though: I'm just getting my K100 knowledge base started.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #5 on: March 03, 2018, 11:51:12 AM »
Further thought on rubber bits.  Rubber bits for BMW bikes are stupid expensive.  Seems to be a lot of competetion for rubber in German industry.  The less you have to buy the more cost effective your rebuild will be.

The big enemy of rubber is Ozone and UV both of which are more plentiful outdoors so if the bike was stored indoors you may not have a lot of damage.  Also, judging from the look of the seat, it appears that the rubber may indeed be in usable shape.


The seat looks great, but the grips & switchgear look like they sat out in the Arizona desert.  I honestly don't know what to expect from the rest of the rubber parts.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Laitch

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Re: '85 RS Porch Ornament Gets New Home
« Reply #6 on: March 03, 2018, 12:12:41 PM »
The seat looks great, but the grips & switchgear look like they sat out in the Arizona desert.  I honestly don't know what to expect from the rest of the rubber parts.
Grips are easily replaced cheaply. As for the switch gear, I'll refer you to this post from prakash's project.
  • 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 Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #7 on: March 03, 2018, 12:19:44 PM »
Grips are easily replaced cheaply. As for the switch gear, I'll refer you to this post from prakash's project.


Thanks Laitch-- I'm just using those components as an indicator of the possible condition of other components.  The switchgear looks ugly but usable, and the grips will suffice for a time.  Their replacement would be the sprinkles on the cake, anyway.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline The Mighty Gryphon

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Re: '85 RS Porch Ornament Gets New Home
« Reply #8 on: March 03, 2018, 12:44:36 PM »
Guys I have done business with through eBay that are in Colorado: 

TD motorcycles, Denver (Ebay Odlidle)

Steeles Cycles, Englewood (eBay Steelescycle)

These guys have good parts, fair prices and seem to have a decent inventory of K-bike stuff.

There's another, but I can't recall who or where.  Pretty much all the breakers on eBay are good to deal with.  But the guys above are brick and mortar and within an hour or so of you.

  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue, '89 K100RS Special edition White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too
'89 K100RS SE

Offline mophead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #9 on: March 03, 2018, 12:46:27 PM »
If you decide its a keeper I have a Supertrapp header and muffler I could part with.  I recently bought a K1100RS and it won't fit because of the bodywork.  Got lucky and found a new Remus and installed it.

Picked up the Supertrapp thinking I would find another K100RS but came across the K1100RS that was really nice so no longer needed.

Regardless hope you get the beast up and running.
  • Amarillo, TX
  • 95 K1100RS Formerly 86 K100RS & 91 K100RS
On the back nine of life

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #10 on: March 03, 2018, 01:06:56 PM »
Guys I have done business with through eBay that are in Colorado: 

TD motorcycles, Denver (Ebay Odlidle)

Steeles Cycles, Englewood (eBay Steelescycle)

These guys have good parts, fair prices and seem to have a decent inventory of K-bike stuff.

There's another, but I can't recall who or where.  Pretty much all the breakers on eBay are good to deal with.  But the guys above are brick and mortar and within an hour or so of you.

Sweetó thank you!
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #11 on: March 03, 2018, 01:09:37 PM »
If you decide its a keeper I have a Supertrapp header and muffler I could part with.  I recently bought a K1100RS and it won't fit because of the bodywork.  Got lucky and found a new Remus and installed it.

Picked up the Supertrapp thinking I would find another K100RS but came across the K1100RS that was really nice so no longer needed.

Regardless hope you get the beast up and running.


Thank you!

What would be the benefit of such a system? Less weight & restriction is what Iím assuming.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Online Martin

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Re: '85 RS Porch Ornament Gets New Home
« Reply #12 on: March 03, 2018, 02:36:00 PM »
Generally more noise at the expense of performance. Previous dyno comparisons have shown virtually no improvement between aftermarket and OEM exhausts. Any improvement in the low mid or top end is countered by a loss elsewhere.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Laitch

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Re: '85 RS Porch Ornament Gets New Home
« Reply #13 on: March 03, 2018, 03:28:43 PM »
Generally more noise at the expense of performance.
Loud pipes save lives!  :sip:
  • 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 mophead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #14 on: March 03, 2018, 10:49:34 PM »

Thank you!

What would be the benefit of such a system? Less weight & restriction is what Iím assuming.

Definitely saves weight.  I would say no performance gain.  I like the sound of them.  Stock is too tame for my tastes.
  • Amarillo, TX
  • 95 K1100RS Formerly 86 K100RS & 91 K100RS
On the back nine of life

Offline Chaos

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Re: '85 RS Porch Ornament Gets New Home
« Reply #15 on: March 03, 2018, 11:20:08 PM »
Definitely saves weight.  I would say no performance gain.  I like the sound of them.  Stock is too tame for my tastes.

Ditto.  I've run stock, Luftmeister, MAC, and Supertrapp.  The S-trap was by far the worst, horrid raspy sound and it covered the rear wheel with soot because it is short and the discs force the exhaust out sideways.  T?he MAC is the nicest sounding and looks good, but none of them increased  hp
  • 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)

Online Martin

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Re: '85 RS Porch Ornament Gets New Home
« Reply #16 on: March 03, 2018, 11:25:44 PM »
All the dyno tests I've seen over the years actually show a decrease in performance. Some a small decrease others larger.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #17 on: March 04, 2018, 12:25:26 PM »
Probably just stick with the stock pipe, then. For some reason, the bike came with an extra one.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Online Martin

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Re: '85 RS Porch Ornament Gets New Home
« Reply #18 on: March 04, 2018, 01:38:37 PM »
Due to the thickness and the quality of the stainless used in the manufacture of the OEM exhausts, they can be brought back to a better than new
condition with work. Wet and dry, scotch pads, brass brush, buffing wheels, cutting compound and copious amounts of elbow grease.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #19 on: March 04, 2018, 02:17:32 PM »
Due to the thickness and the quality of the stainless used in the manufacture of the OEM exhausts, they can be brought back to a better than new
condition with work. Wet and dry, scotch pads, brass brush, buffing wheels, cutting compound and copious amounts of elbow grease.
Regards Martin.

Thanks Martin. Thatíll be way down the list of things I can now do because...
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #20 on: March 04, 2018, 02:22:06 PM »
...all seems well here:





I found a bit of oil inside (1/4 tsp maybe), and I thought I was going to lose the fight with lower inside bolt, but otherwise all went well with the removal.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #21 on: March 04, 2018, 02:27:39 PM »
Blurbed up:



My oilfield pack of anti-seize stood me in good stead because thereís no moly-fortified paste available in this burg.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Online Martin

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Re: '85 RS Porch Ornament Gets New Home
« Reply #22 on: March 04, 2018, 02:38:16 PM »
You can get the Honda M77 assembly paste from Honda car and motorcycle dealer parts department. And I have been told Subaru either use it or their own version.
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #23 on: March 04, 2018, 02:52:57 PM »
Took the opportunity to hit these connections with electronic cleaner & dielectric grease while I was in the neighborhood:



On an unrelated note, I also noticed that the steering head bearings seem to be binding up, so servicing them gets added to the list.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

Offline Nailhead

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Re: '85 RS Porch Ornament Gets New Home
« Reply #24 on: March 04, 2018, 02:59:00 PM »
You can get the Honda M77 assembly paste from Honda car and motorcycle dealer parts department. And I have been told Subaru either use it or their own version.
Regards Martin.

Not at our local Honda car dealer: they quit carrying it, and there isnít a Honda motorcycle dealer within miles. The Subaru option I was not aware of.

Thanks Martin.

Happen to know the torque specs for the final drive & caliper bolts offhand?  I forgot that info at home.
  • Longmont, CO
  • 1985 K100RS
'85 K100RS, '07 KTM 990 Adv., '93 Ducati 900SS, '87 Suzuki SP 200, '80 BMW R100RS, '7? Benelli 650S

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