Author Topic: An idiot and his first bike  (Read 95899 times)

Offline Nantucket_Red

  • ^ Motobrick Curious
  • Posts: 62
Re: An idiot and his first bike - cafe conversion
« Reply #50 on: May 17, 2015, 08:45:01 PM »
Loving this build so far. Keep going!
  • Cape Cod,MA
  • 1987 BMW K100RT

Offline telecaster-custom

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  • Posts: 5
Re: An idiot and his first bike - cafe conversion
« Reply #51 on: May 19, 2015, 10:47:04 AM »
Hope you're still updating on this build!

Couple of quick questions:

- what headlight did you use?  it looks great.

- are you planning on going without instruments/gauges or do you have a plan for adding those?  I'm trying to find suitable analog-style gauges for my K75 and not really finding good info.
  • Cleveland, OH
  • 1991 K75S

Offline Andrewck

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Re: An idiot and his first bike - cafe conversion
« Reply #52 on: May 26, 2015, 06:07:29 PM »
Hope you're still updating on this build!

Couple of quick questions:

- what headlight did you use?  it looks great.

- are you planning on going without instruments/gauges or do you have a plan for adding those?  I'm trying to find suitable analog-style gauges for my K75 and not really finding good info.

DCC sells a 7.0" headlight that I purchased and wired up myself.

Absolutely plan on installing new instruments.  Would like to sell my old ones before plunking down the cash on a new set.  If you've got the moolah, Motogadget makes and incredibly gorgeous set of analog instruments.  Most BMW cafe conversions I've seen use Acewell units and it sounds like they are relatively easy to wire up.  With the aggressive lines of the K bikes, it's hard to incorporate a round speedometer (or anything round really) into the shape of the bike.  Good luck and let me know what you go with.
1990 K75S

Offline rbm

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Re: An idiot and his first bike - cafe conversion
« Reply #53 on: May 26, 2015, 06:59:59 PM »
I managed to integrate a round instrument in a square K
  • Regards, Robert
Toronto, Ontario

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

Offline Andrewck

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Re: An idiot and his first bike - cafe conversion
« Reply #54 on: May 26, 2015, 07:17:00 PM »
And you've done a great job.  Not saying it's impossible, but it takes a lot of thought and planning to do it right and make it flow with the rest of the bike.
1990 K75S

Offline sj2000

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  • Posts: 133
Re: An idiot and his first bike - cafe conversion
« Reply #55 on: May 27, 2015, 12:43:24 PM »
RBM, I like that headlight bucket with the speedo, found it in benji cafe racer: http://www.benjiescaferacer.com/headlight-bucket.php. trying to find in internet how to do it using fiberglass but nothing.
  • Parker, USA
  • 1985 K100

Offline rbm

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Re: An idiot and his first bike - cafe conversion
« Reply #56 on: May 27, 2015, 04:52:39 PM »
Thanks.

The headlight nacelle I used is a real vintage BMW R52/2 headlight bucket from 1955.  I also bought real vintage BMW headlight mounting ears.  I refurbished the bucket and modified the ears to fit the K1100 forks I used.  Then I got the whole shebang painted.

The bucket from Benji cafe racers will work but check with them first to make sure the instrument hole is the right size.  The Motogadget Classic gauge is exactly 80.0mm in diameter.
  • Regards, Robert
Toronto, Ontario

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

Offline jenkinskg

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Re: An idiot and his first bike - cafe conversion
« Reply #57 on: May 28, 2015, 05:27:31 PM »
Got another k75, this one had minor issues and was older naked version.
18" wheels front and back, 1986

I forgot how nimble the bike is, after riding the k1200lt so much so

Offline Nantucket_Red

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Re: An idiot and his first bike - cafe conversion
« Reply #58 on: July 05, 2015, 06:51:19 PM »
Any more progress? It was just getting good  :popcorm
  • Cape Cod,MA
  • 1987 BMW K100RT

Offline Andrewck

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Re: An idiot and his first bike - cafe conversion
« Reply #59 on: July 16, 2015, 10:29:56 PM »
After a healthy amount of summer travel, I was able to find some time to work on the bike and knock off a few projects.

Frame
After receiving a shop estimate of ~$400 to cut the frame and weld it, I decided I could do it myself.  I eyeballed where I wanted the frame cut, put down a few pieces of electrical tape as a mark and had at it.  Since I don't have a proper reciprocating saw, I ended up using my drill with a cut off wheel...or 3 of them.  Totally turned out to be a crude hack job that needs a little TLC to spruce things up, but it got the job done and the daunting task of shortening the frame is behind me.  Yet to put black plugs on the frame to keep water out, but that's easy.  Not sure if I need to reinforce the frame further, but I'll ride the bike for a while and see if I notice any flexing or stability issues while cornering.

One of the best parts of cutting the frame off was hammering the hell out of the seat locking mechanism.  I started to cut it with a cut off wheel, but it proved to be a tough angle and I was worried about nicking the frame.  Out came the hammer and I spent the next 5 minutes getting out my aggression!  Finally the entire thing popped off and was sent flying across my garage floor with a satisfying clang.  I've still got to de-tab the frame further, but that's for another day and another beer.

Seat
Gone is the Bondo-covered seat and here is the primer-covered seat.  I picked up some Rustoleum primer filler and made about 5 passes on the seat, using 400 grit sandpaper between coats.  I finally got the seat to where I feel comfortable painting it.  Like I've said...this is not the permanent seat so I'll end up painting it myself with some Duplicolor.  My friend uses CAD on a daily basis and has access to an industrial-sized 3D printer.  Our plan is to take my seat, enter it into CAD, refine the shape (so it's not uneven) and print off the seat using industrial polymer.  It will still be very lightweight and should provide more than enough structural support.  Since the 3D printer will print the seat pan as a solid piece, I'll be able to remove the wooden chair bottom after v2.

I will post updates and photos of the v2 seat, but for those who interested, I will be able to print out copies of the seat since it's in CAD.  If you're interested in purchasing the K75 cafe racer seat, please PM me and we can discuss.

Electronics
Screw holes to secure the taillight into the seat were drilled.  Electronics have been hidden below the shell for now.  After riding in the rain today, I realize I'll need a little more protection from the elements underneath.

I am fooling around with the idea of rerouting the horn wiring to the storage case below the seat and hooking it up to a garage door remote.  Haven't researched this at all, but I would like to be able to trigger the horn and have the garage open.  Pipe dreams...

Sadly the rear turn signals just aren't that bright and since they're integrated into the taillight, they are fairly close together.  I'd like a little more spacing on them and for them to match the front of the bike.  Ordering an additional set of turn signals for the rear to match the front set.  Will have to fabricate some kind of holder for them in the back.

Speedometer
Still waiting to sell my old, fully functional speedometer to finance a new one.  I'm pretty much decided on the black Acewell speedometer/tachometer.  Yes, every BMW cafe racer has one, but I like the look and I can't find anything better.  If you've got a suggestion, I'd love to hear it.

Exhaust
No idea what I'm going to do here yet.  Thinking of wrapping the headers in black heat wrap and getting a black megaphone exhaust.  It needs to be shorter than the stock muffler since the bike is about 15" shorter.  Again, suggestions here are welcome.
1990 K75S

Offline Nantucket_Red

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  • Posts: 62
Re: An idiot and his first bike - cafe conversion
« Reply #60 on: July 17, 2015, 07:19:23 PM »
Getting an exhaust is difficult for these bikes. BSK makes a 4 to 1 collector with a 2'' OD I believe. Finding something that'll fit with that has been difficult as well.
http://www.bskspeedworks.co.uk/k-collector.html

  • Cape Cod,MA
  • 1987 BMW K100RT

Offline Andrewck

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  • Posts: 95
Re: An idiot and his first bike - cafe conversion
« Reply #61 on: July 19, 2015, 08:16:12 PM »
Wish that worked...I've got a K75 and need a 3-to-1 collector.  Possible to just remove my muffler and go with straight pipes?  Would my bike be able to run without the backpressure?
1990 K75S

Offline rbm

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  • Posts: 2281
Re: An idiot and his first bike - cafe conversion
« Reply #62 on: July 19, 2015, 09:18:14 PM »
The K75 header is designed such that it merges the three exhaust pipes into one 41mm diameter outlet pipe.  It's not possible to run three straight pipes (if that's what you're thinking) unless you're going to weld them up from scratch.  If you're after an all-black look from the block to the muffler, then ditch the wrap and get the headers ceramic coated.  As for the muffler, what's your objective with changing from stock?  Looks? Sound? Performance?
  • Regards, Robert
Toronto, Ontario

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

Offline Andrewck

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Re: An idiot and his first bike - cafe conversion
« Reply #63 on: July 22, 2015, 03:13:39 PM »
Let me clarify...as I do not wish to run straight pipes from each of the 3 headers.  I wanted to cut the stock muffler off and run an outlet (or straight pipe) from the collector.  The idea of removing the muffler is 3 fold:

Looks (I don't enjoy the bulky look of the stock piece)  I also don't want a giant aftermarket can on there and just not sure if a megaphone muffler would work with the look of my bike.

Weight (Any weight savings is good weight savings).  The bike is already more responsive without the plastic on there and if I can squeak out a few more pounds, I certainly wouldn't mind.

Sound (while I don't feel the need to scream for attention, I would like the bike's exhaust to be a little louder).  Am I correct in that removing the muffler and not replacing it with anything would make the bike slightly louder?

My worry comes from doing damage to the engine because of no backpressure and ruining air/fuel mix
1990 K75S

Offline bikesnbones

  • ^ Proficient Motobricker
  • Posts: 113
Re: An idiot and his first bike - cafe conversion
« Reply #64 on: August 17, 2015, 12:34:00 AM »
My name is Andrew and I am an idiot.

I agree, and if no one else is going to say it, I will.
You've taken what appeared to have been a lovely standard motorcycle, and ruined it, to the point where it now looks like something lashed back together from the parts bin after a major crash.
Such a shame.



  • Peterborough UK

Offline Glacial

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  • Posts: 158
Re: An idiot and his first bike - cafe conversion
« Reply #65 on: August 17, 2015, 05:17:41 AM »
bikesnbones: to be fair to Andrew, he did warn those of us who think the BMW designers really got it right with the K75S that he was going to do something we wouldn't like and to look away now. Parents still love their babies, whatever they look like. I don't understand the cafe racer thing myself and as I have said in another post, it takes a design genius to make one look good. We mourn the loss of another good-looking bike and move on....
  • Cambridge, UK
  • 1990 K75S VIN 0109678
'If this is your mid-life crisis, you are going to live to be 114'

Offline The Mighty Gryphon

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Re: An idiot and his first bike - cafe conversion
« Reply #66 on: August 17, 2015, 08:31:35 AM »
While most of us appreciate the design of the S model, IMO it's styling is grossly out of place in the urban/ghetto environment.  Cafe bikes are not used for smoothly and comfortably traveling long distances through open country.  They are intended more for day to day travel in the world of potholed pavement, stop-and-go traffic, and graffiti.   For where most of these cafe conversions spend their lives, they are the perfect adaptations to blend seamlessly with their environment. 

One should think of them more as a cross between an urban assault vehicle and street art.
  • 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 bikesnbones

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  • Posts: 113
Re: An idiot and his first bike - cafe conversion
« Reply #67 on: August 17, 2015, 03:37:32 PM »
bikesnbones: to be fair to Andrew, he did warn those of us who think the BMW designers really got it right with the K75S that he was going to do something we wouldn't like and to look away now. Parents still love their babies, whatever they look like. I don't understand the cafe racer thing myself and as I have said in another post, it takes a design genius to make one look good.

My apologies for my strong words, but this sort of thing really does boil my piss.
It's just that there are no end of old shitters out there that were made to satisfy this new hipster café craze, which is why it hurts so much to see great modern classic succumb to this nasty end.

 :cowpoop:

We mourn the loss of another good-looking bike and move on....

Indeed we do.

  • Peterborough UK

Offline JcJ TN K75s

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  • Posts: 77
Re: An idiot and his first bike - cafe conversion
« Reply #68 on: August 17, 2015, 10:37:07 PM »
 I really don't see anything to mourn. If you want to preserve K75s, now is the time to do it. Maybe some of y'all ain't noticed, but you can't give em away these days.
Run with it Andrew. Haters gonna hate.
  • Lincoln, TN 37334
  • 1993 K75S? "Stormtrooper" 1999 R1100RTP "Lord Vader"
I am quite sure now that often, very often, in matters concerning religion and politics a man’s reasoning powers are not above the monkey’s.- Mark Twain

It could probably be shown by facts and figures that there is no distinctly native American criminal class except Congress.-
Mark Twain

Offline bikesnbones

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Re: An idiot and his first bike - cafe conversion
« Reply #69 on: August 18, 2015, 05:27:30 PM »
I really don't see anything to mourn. If you want to preserve K75s, now is the time to do it. Maybe some of y'all ain't noticed, but you can't give em away these days.
Run with it Andrew. Haters gonna hate.

It's a very ignorant person who judges the true value of a classic in monetary terms.
  • Peterborough UK

Offline JcJ TN K75s

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  • Posts: 77
Re: An idiot and his first bike - cafe conversion
« Reply #70 on: August 18, 2015, 05:57:03 PM »


It's a very ignorant person who judges the true value of a classic in monetary terms.
Its a very emotional person who thinks what he believes is a "classic" has any bearing on value. If Flying Bricks are so undervalued, then there is a great investment opportunity for you. Buy em up and store them until everyone else realizes what a mistake they've made.  I would love to add one or two more to my stable, and will probably sell my Oilhead soon to make room for another FB.
The CB/KZ/GN/GS guys all cry about the same thing, and it does them just as much good. 
A bike that goes tons project builder, who will learn its peculiarities and share what he learns on the web with the rest of us is much more valuable than a bike that goes to a breaker or a scrapyard, and if they aren't worth any money, that IS where they will go. If we don't come through with a higher bid, that's on us, too,  brother.
  • Lincoln, TN 37334
  • 1993 K75S? "Stormtrooper" 1999 R1100RTP "Lord Vader"
I am quite sure now that often, very often, in matters concerning religion and politics a man’s reasoning powers are not above the monkey’s.- Mark Twain

It could probably be shown by facts and figures that there is no distinctly native American criminal class except Congress.-
Mark Twain

Offline bikesnbones

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  • Posts: 113
Re: An idiot and his first bike - cafe conversion
« Reply #71 on: August 18, 2015, 06:26:42 PM »
Its a very emotional person who thinks what he believes is a "classic" has any bearing on value.

You're just not getting this are you.
I couldn't care less about value.
Neither does any other REAL enthusiast.
Bike investors are the scourge of our passion.
They care not one jot about the bike, other than what return it will give them on their investment.
That's not what a real enthusiast cares about,
There's so much more to it.
Please don't tell me I have to explain that to you.
 :yow
  • Peterborough UK

Offline JcJ TN K75s

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  • Posts: 77
Re: An idiot and his first bike - cafe conversion
« Reply #72 on: August 18, 2015, 06:43:41 PM »
You're just not getting this, are you? No one cares that it makes you butthurt that your fond feelings for Flying Bricks preservation is not reflected by everyone else. It is of absolutely no relevance, and no importance. Your tone is one to be expected from a whiny, jealous child. Get over it. Or don't. It doesn't make a difference either way, to anyone but you, and you are not superior to anyone else on this forum. Grow up.

Maybe you didn't notice that this subforum is called "Project K Bikes.......chronicle your k project and cafe builds.....". If it hurts your delicate sensibilities so much, turn your eyes away. But know that if you continue to make a public spectacle of yourself while you cry and rend your garments, I will continue to point and laugh.
  • Lincoln, TN 37334
  • 1993 K75S? "Stormtrooper" 1999 R1100RTP "Lord Vader"
I am quite sure now that often, very often, in matters concerning religion and politics a man’s reasoning powers are not above the monkey’s.- Mark Twain

It could probably be shown by facts and figures that there is no distinctly native American criminal class except Congress.-
Mark Twain

Offline MonkeyMcBean

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  • Posts: 137
Re: An idiot and his first bike - cafe conversion
« Reply #73 on: August 18, 2015, 09:03:55 PM »
I forgot how nimble the bike is, after riding the k1200lt so much so

Put some s bars on it and you'll know what nimble is.
  • North Dakota, USA
  • 1993 k75s
This is it. F*** it. It is what it is.

Offline MonkeyMcBean

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  • Posts: 137
Re: An idiot and his first bike - cafe conversion
« Reply #74 on: August 18, 2015, 10:07:38 PM »
Quote
  Am I correct in that removing the muffler and not replacing it with anything would make the bike slightly louder?

You're right. Here's a video from another user.

Pulled exhaust of, did a short pull.  :falldown:


  • North Dakota, USA
  • 1993 k75s
This is it. F*** it. It is what it is.

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