Author Topic: Starting the research on R80 and K75  (Read 8922 times)

Online The Mighty Gryphon

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Re: Starting the research on R80 and K75
« Reply #25 on: July 14, 2018, 10:04:28 AM »
Why be ashamed of K-smoke.  That cloud of oil mist wafting gently downwind is providing a nano film of rust preventative to anything it envelopes.  Not to mention the flying insect control.

You are doing a public service... 
  • In my garage in Marilla, NY
  • '94 K75RT Mystic Red, '91K100RS White/Blue
Current:
'94 K75RT "Ilsa, She Wolf of the SS"
'91 K100RS "Moby Brick Too

Offline stokester

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Re: Starting the research on R80 and K75
« Reply #26 on: July 14, 2018, 12:34:51 PM »
after decades of using the centerstand I've relegated it now pretty much just for maintenance use.  Stories of it collapsing and general laziness are the culprits.  Two tricks to using the sidestand, tilt the bike to the right for a moment after shutting it off, and before starting it back it out of it's spot so you can drop it into gear and have a clean getaway, avoiding the glares and criticisms of onlookers and they succumb to a cloud of K smoke.  Actually, mine only smokes maybe 1 out of 10 times, no rhyme or reason.   :dunno
Me too.  I feel the bike is more stable on the sidestand after finding my K75 sunk into the asphalt up to the foot pad when using the centerstand.  I always carry a pad for the sidestand to prevent that sinking feeling on questionable surfaces.

It smokes on startup about the same frequency as my airheads which is not very often but when it does there always seems to be an audience  :mbird
  • Yorktown, Virginia
  • '94 K75S - '93 K75S - '91 R100RT - '78 R100S

Offline Adam M

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Re: Starting the research on R80 and K75
« Reply #27 on: July 14, 2018, 03:24:18 PM »
I took a look at very nice 92 K75S this afternoon, had an opportunity to seat on it and put it on the center stand.
I didn't ride because of constant rain. No problem at all with center stand it, I can do it in my sandals easily.
I checked the bike quite extensively and it looks very well taken care for. Only problem I see is original position with very short handlebar which is placed too far forward to my liking. Current owner told me I can use some kit to rise it a bit and place it back, without changing a length of a brake hose.
Did anybody used it and with what result ?
  • Canada
  • Triumph T 150 Trident.

Offline Chaos

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Re: Starting the research on R80 and K75
« Reply #28 on: July 14, 2018, 04:12:05 PM »
I've have the barbacks he's referring to, that little bit up and back made a huge difference to me.  Usually the brake line will be fine. Search ebay and vendors   https://www.panjo.com/buy/handlebar-riser-bar-backs-for-k75-k100-bmws-197854
  • 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 stokester

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Re: Starting the research on R80 and K75
« Reply #29 on: July 14, 2018, 04:30:21 PM »
<SNIP>
Only problem I see is original position with very short handlebar which is placed too far forward to my liking. Current owner told me I can use some kit to rise it a bit and place it back, without changing a length of a brake hose.
Did anybody used it and with what result ?
I find the K75S ergonomics near perfect for my nearly 6' frame and long arms but know that it is too far forward for many.

There will probably be others who chime in that the handlebars from a K75C meet the need.
  • Yorktown, Virginia
  • '94 K75S - '93 K75S - '91 R100RT - '78 R100S

Offline blackie1

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  • christchurch nz
Re: Starting the research on R80 and K75
« Reply #30 on: July 14, 2018, 05:14:31 PM »
don't worry about the handle bar position, after all you have only sat on it for wat... a minute.
anything new to you will feel different.
ride it for a month and it will fit u like an old glove. humans have been adapting for millenia, although some would say the aussies have timed out on their adaptation duties.

of course i would never say that
 :clap:
  • new zealand , where else would u want to live, really
  • 1991 K75RT naked 40,000kms

Offline Martin

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Re: Starting the research on R80 and K75
« Reply #31 on: July 14, 2018, 05:28:08 PM »
Before buying new bars try adjusting them, as you rotate them back they also come up. I've adjusted mine progressively over the years. The last modification involved spacers moving the bars up 1" and back 1".

Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline blackie1

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  • christchurch nz
Re: Starting the research on R80 and K75
« Reply #32 on: July 14, 2018, 05:55:08 PM »
martin i am shattered i could not get a rise out of u lol
  • new zealand , where else would u want to live, really
  • 1991 K75RT naked 40,000kms

Offline rbm

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Re: Starting the research on R80 and K75
« Reply #33 on: July 14, 2018, 06:18:11 PM »
Contact me, Adam, if you want me to accompany you to do a once-over.  Hopefully it's not in Kanata or London or somewhere else well outside the GTA. :)
  • Regards, Robert
Toronto, Ontario

1987 K75 - Build Blog @http://k75retro.blogspot.ca/

Offline Martin

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Re: Starting the research on R80 and K75
« Reply #34 on: July 14, 2018, 06:24:50 PM »
Blackie since I have now retired nothing that mild will get a rise out of me. I could make a crack about Kiwis, but it would be too easy and be a cheap shot. :neener:
Regards a totally cooled out Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline duckhawk

  • duckhawk
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Re: Starting the research on R80 and K75
« Reply #35 on: July 14, 2018, 11:09:52 PM »
I have owned both. I had an 81 R80RT.

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The R80RT was truly an amazing bike. The ergonomics were perfect for me. It was so perfectly balanced I could ride no handed and, lean only, on long radius turns for literally miles at a time.

I had to sell it to get the 02 1150 and I sold it for more than I paid for it.

The boxer engine was not smooth at low RPMS and shook the bike when lugged, but sang at 50-80mph. The tranny was unforgiving and took a while to master. Compared to the sewing machine precision of the K75's engine and gearbox, the R80's engine was clunky. The 1150's is the same way. 2 pistons mashing out brute force power when stomped on. Nothing like the steady roll on of the K75 , at any rate.

Once, after not checking the tire pressure, I bounced  the R80 hard off a curb on a left turn, AND IT BOUNCED ME BACK ON THE ROAD. After that day I swore I would own nothing but a boxer.

In contrast, another time I wound it hard up the gears while touring in a rain storm and it popped out of gear between 4th and 5th at 80MPH and scared the hell out of me.

Bottom line, the low center of gravity was a complete joy, saved me once, and that's why I own the 1150.


The K75 is different. I bought it, sight unseen, and flew out to the Carolinas and rode it back to Wisconsin in 2 days of super-slab riding. It took me a while, but after the used scout fairing, I found myself riding it 80% of the time. Mostly because of the smoothness, less weight, less shifting with the expansive powerband. It is my CITYBIKE.

Now, I am training my son to ride. He is an amateur dirtbiker, so he has some riding skill, but I trust the K75's smoothness and steadiness to help him along.

Wrenching. To me it takes the same skill level to do both bikes. I have always adjusted my own valves, basic maintenance, etc. Vintage dirtbike maintenance is simplistic compared to these roadbikes. But with all the info the sites like this, you can learn to do most of the non-major stuff.


Why buy one, when you can buy two for twice the price!!
  • Cowconsin
  • 95 K75
"Go soothingly on the grease mud as there lurk the skid devil."

 In Clancy's Boots: The Greatest Ever Round-The-World Motorbike Adventure.
 - Geoff Hill

Offline Adam M

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Re: Starting the research on R80 and K75
« Reply #36 on: July 14, 2018, 11:16:23 PM »
Hi rbm it's in Newmarket, I wouldn't feel well to pull you all the way there.
I plan to go there on my bike, to try it as long as my body remembers the last BMW :).
The current owner is very particular, he has all recites and hand written blog of anything done to the bike over the years.
  • Canada
  • Triumph T 150 Trident.

Offline Skunky

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Re: Starting the research on R80 and K75
« Reply #37 on: July 15, 2018, 07:43:16 PM »
 [ Invalid Attachment ]   :hehehe
  • Derby GB
  • BMW K100lt
Rebuild it and they will come..
90 K100lt
Triumph Thruxton 900
Honda CB400F

Offline bocutter Ed

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Re: Starting the research on R80 and K75
« Reply #38 on: July 16, 2018, 10:34:38 AM »
it's in Newmarket
That's only an hour North of us not taking the slab. I'll go here www.milbreeviking.com for a doughnut ...
  • Toronto, Canada
  • '61 Puch DS60 - '66 Puch 250 SGS - '87 BMW K75s

Offline Martin

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Re: Starting the research on R80 and K75
« Reply #39 on: July 16, 2018, 03:20:38 PM »
Arhhhhh, Donuts. :lets-eat:
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline bocutter Ed

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Re: Starting the research on R80 and K75
« Reply #40 on: July 16, 2018, 03:39:15 PM »
Arhhhhh, Donuts. :lets-eat:
This bakery also makes ground meat filled donuts (no sugar in the dough).  :lets-eat:
  • Toronto, Canada
  • '61 Puch DS60 - '66 Puch 250 SGS - '87 BMW K75s

Offline Adam M

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Re: Starting the research on R80 and K75
« Reply #41 on: July 16, 2018, 03:57:50 PM »
I'll take it under consideration, however this bakery is closed until July 18.
  • Canada
  • Triumph T 150 Trident.

Offline bocutter Ed

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Re: Starting the research on R80 and K75
« Reply #42 on: July 16, 2018, 04:10:26 PM »
Yup, reopens Thursday. I have a Ride Leader training session at noon Thursday.
  • Toronto, Canada
  • '61 Puch DS60 - '66 Puch 250 SGS - '87 BMW K75s

Offline Martin

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Re: Starting the research on R80 and K75
« Reply #43 on: July 16, 2018, 04:11:08 PM »
Ed Why that's like putting ground beef in a chocolate éclair. :nono :musicboohoo:
Regards Martin.
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline bocutter Ed

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Re: Starting the research on R80 and K75
« Reply #44 on: July 16, 2018, 04:55:01 PM »
Nah, it's more like a sausage roll, sans the flakey pastry, stuffed in a savory donut. Once I went in for a fruit donut and Liisa the baker had made them with the 'other' dough = half price.

I remember having an éclair at Harrods when I was a child. Asked Granny if I could have another, ever so politely ... yesss!
  • Toronto, Canada
  • '61 Puch DS60 - '66 Puch 250 SGS - '87 BMW K75s

Offline bocutter Ed

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Re: Starting the research on R80 and K75
« Reply #45 on: July 16, 2018, 04:58:43 PM »
[ Invalid Attachment ]   :hehehe
Woodn't those boots be an impediment to being shifty.
  • Toronto, Canada
  • '61 Puch DS60 - '66 Puch 250 SGS - '87 BMW K75s

Offline Martin

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Re: Starting the research on R80 and K75
« Reply #46 on: July 16, 2018, 05:06:11 PM »
Ed Beefy's pies make the best eclairs ever, proper chocolate, cream filled we have two 5 min in either direction. :lets-eat:
Regards Martin
 [ Invalid Attachment ]
  • North Lakes Queensland Australia
  • 1992 K75s Hybrid, Lefaux, Vespa V twin.

Offline Adam M

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Re: Starting the research on R80 and K75
« Reply #47 on: July 17, 2018, 08:26:31 PM »
Two more questions.
The bike I'm going to see tomorrow ( 92 K 75S ) doesn't have an ABS. Pumps are removed by the previous owner.
What can I expect from ABS lamp ?
What is minimal thickness of rotors ?
This bike has 3 of them and front ones look pretty thin to me.
  • Canada
  • Triumph T 150 Trident.

Offline rbm

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Re: Starting the research on R80 and K75
« Reply #48 on: July 17, 2018, 08:55:06 PM »
If the ABS is completely removed, that should include the ABS brain located in the tail compartment.  The ABS light should be extinguished if so.

The minimum brake disk thickness is 3.6mm.  I believe a new disk is 4.5mm (taking a guess here).

Update:  Looked it up. A new disk is  4.0mm
  • Regards, Robert
Toronto, Ontario

1987 K75 - Build Blog @http://k75retro.blogspot.ca/

Offline Adam M

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Re: Starting the research on R80 and K75
« Reply #49 on: July 17, 2018, 09:11:11 PM »
Thanks rbm.
I'm used to around 5 mm in old Japanese bikes.
  • Canada
  • Triumph T 150 Trident.

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