Back in the days, the K100RS was advertised as a sport tourer bike. Well, tourer ok, sport...not really, even if it was really efficient, in spite of a relatively modest power.
So some tried to improve this sport side, with parts or accessories made for the K100. Few companies, in fact...Wüdo, Fallert, Wulf Gerstenmaier made a wonderful sport K100, Luftmeister in the USA with turbo kits...but that's all.
With no support from the factory in road racing championships, nobody wanted a look alike bike, so sport parts designed for K100 are quite rare. The BMW catalog only offered a one person sport seat, sport footpegs and sport suspension from White Power.
Rovering in european swap meets, I found some of these  parts, year after year, collecting them, hoping to find one day time to build an 80's racer replica.
And then Covid 19 arrived!
Yeah! Plenty of free time, a big garage, a lot of spares and the basis, a damaged 1989 K100LT, bought last summer for 300€...let's start.
Goal: build a sport K100, only with dedicated parts from the eighties. No chinese crap made for today's  shorttailed "racers", no led lights, no digital speedo, and no fucking diarrhea colored short tail .

After installing new fork tubes and overhauling the dampers, a Telefix link was installed to get this fork more rigid. I could have installed a Showa fork from a K75...but I prefered this option, that allowed me to change also the front mudguard.
3 spoke optionnal wheels, named "sport wheels" in BMW part list, but in fact heavier than Y spoke wheels, were installed. Renewed brakes, the ABS is still in place, until I can test it on road. If it's out of order, as I'm awaiting, I'll remove it to save weight (14kg).
Then the engine was serviced, with a full new injection line from the pump to the injectors.
The exhaust comes from France, Recchia, a BMW dealer from Lyon, made by Bobopot, an exhaust maker nearby. Street legal, different sound but not too noisy.
I found K100 rearsets from ABM and the Fallert seat in a small swap meet I'm visiting monthly not very far from home. Very unlikely to find these rare parts there...but they were.
The footpegs are uncomplete, so I had to install a master cylinder outside with a direct command, instead of the original device. Too big (16mm Nissin instead of the 12mm Lagura) for the caliper, it's almost inefficient. But the Covid lockdown made it difficult to find the good parts...I'll change it later.
The seat was a 2 person, but the passenger seat was missing. So an new foam and new upholstery were made to create an single person seat.
The rear damper was changed for an Ohlins shock, with a new spring.
A K75S handlebar was fitted. Clips on bars could have replace it, but I'm getting too old to cope with this position
For the fairing, I first tried a Ducati half fairing. Good looking...but not the spirit, and so many time used and seen. So I used a half RS fairing, with no side panels nor radiator cover, but it was tilted forwards, for a more sporty line, with home made brackets. I had planned to install a smaller rectangular headlight, but found that the windscreen shape was eventually too complex for my skills to extend it from a polycarbonate sheet. I've been searching a twin round headlight from Wüdo, with no success.

Then today: first start, and first ride!





Very short and prudent ride, as the temperature today is so hot that I could not do a real test ride wearing only shorts and T shirt. But the few kilometers I rode were enough to enjoy the good and honest behavior of the bike. Excellent roadhanding, lighter than my basic K100, good position. The engine needs some ajustments at idle, but it revs quite well!

I absolutely love the way you've set yourself a very specific theme for the bike - 'exotic eighties'. It seems to be true to the bike, and much more likeable than inflicting an unsuitable 2020 makeover on a stately veteran. The K is a landmark bike; so much more than a coat-hanger for this year's fashion.
Nice one 

+1.

+another 1

Always beautiful builds Jbt!  Your knowledge of the obscure aftermarket options amazes me equally as much as your ability to find these parts.

About this search skills, let me tell you a story.
7 years ago, I was starting a business, opening a garage dedicated to airheads.
I was spending a lot of time wandering for NOS special parts, buying stocks from dealers, so my wife had enough and kidnapped me for a holydays week in Marroco, sort of  rehab .
We were hiking in the Atlas mountains, and she asked me: "So? Don't you fell good now and here, not thinking about BMW parts, in the middle of nowhere?"
I was about to answer when I saw somethin on the ground, in the gravel: A round BMW emblem.
"Are you kidding me?"
She never agreed that it was pure hasard and that I did not throw it there on purpose.
Once I collected it, we heard a roaring engine coming.
A brand new R1250GSLC approached.
Then a second.
Then a third, then 4, 5, 6 etc.
She looked at me like she would consider  me being a sorcerer.
BMW had planned at this place a test week for worldwide dealers for the new GS release.
We met them all the week long, we had exactly the same schedule, even at hotel, even in Marrakesh souk.

chris846 wrote:I absolutely love the way you've set yourself a very specific theme for the bike - 'exotic eighties'. It seems to be true to the bike, and much more likeable than inflicting an unsuitable 2020 makeover on a stately veteran. The K is a landmark bike; so much more than a coat-hanger for this year's fashion.
Nice one 

Couldn't have put it better myself Chris 

jbt wrote:About this search skills, let me tell you a story.
7 years ago, I was starting a business, opening a garage dedicated to airheads.
I was spending a lot of time wandering for NOS special parts, buying stocks from dealers, so my wife had enough and kidnapped me for a holydays week in Marroco, sort of  rehab .
We were hiking in the Atlas mountains, and she asked me: "So? Don't you fell good now and here, not thinking about BMW parts, in the middle of nowhere?"
I was about to answer when I saw somethin on the ground, in the gravel: A round BMW emblem.
"Are you kidding me?"
She never agreed that it was pure hasard and that I did not throw it there on purpose.
Once I collected it, we heard a roaring engine coming.
A brand new R1250GSLC approached.
Then a second.
Then a third, then 4, 5, 6 etc.
She looked at me je like she would consider a sorcerer.
BMW had planned at this place a test week for worldwide dealers for the new GS release.
We met them all the week long, we had exactly the same schedule, even at hotel, even in Marrakesh souk.

Haha - that's great 

New pics this evening:

Those are two of the most beautiful images I have seen of K bikes, ever.  The lighting, the surrounds and the presentation of the subject.  

Merci beaucoup, M'sieur.

Yup ^^^^^gorgeous!!  And a great story too

The light was pretty nice this evening, a huge wall of storm clouds reflecting the sunset colors, enhancing the body lines and shape of the K.

I missed the unicorn matching the colors of the sky, but I saw the Giant Crocodile, emerging from the sea of clouds at dusk, hunting for its prey...

Very nice photos of a really great bike.

If I might offer a tip to anyone wanting to take photos of their bike.  Try to keep the camera 1 meter or less above the ground.  My best photos are with the lens at about 70-80cm.  That is how the pros get those nice images, and is one of the things that makes these photos look so good.

I love the pinstriping on the fairing. White on black.

In a previous life my 16v was silver (more like white) with a blue pinstripe. When I went all black I considered adding the same pinstripes (but in white), but didnt know how to do it.

Bonzo wrote:I love the pinstriping on the fairing. 

Yes!! and I really like how the white piping on the seat works with it too.  JBT you will have to show us the different bikes that you have modified.  Based on the K75GS and this K100 Racer I'm guessing that there might be few others tucked away that are unique as well.

Bonzo wrote:I love the pinstriping on the fairing. White on black.

In a previous life my 16v was silver (more like white) with a blue pinstripe. When I went all black I considered adding the same pinstripes (but in white), but didnt know how to do it.

You tube tutorials,fiddly but manageable

I also wanted to pinstrip  the rear fairing, to emphasize its shape.
But...it's not pinstripping for now, simply a thin tape to test how it looks before real painting.

And Woodie, yes, I have other modified K's...
particularly this one:





It pairs with another K with sidecar, a K1:


I did not modified it much, nature did it...rust has attacked it a lot, as the previous owner used it only for winter rides, on salted roads. And with 225 000 km on the odometer, it's aging, but still runs well. Excellent roadholding, thanks to the width and the special front end.

I wanted to restore it, but it's a long work...

With just 2 wheels, I have also a '85 basic K100, with no spectacular modifications, just a crash bar, a WP rear shock and, depending of the use, a BMW sport seat, a '95 K1100LT and a fully restored K1. And many others BMWs or other brands.
I think that the next K I'll modify will receive a King's fairing.

Not to hijack this thread, but 3M makes a good pinstriping tape.  Works well for making multiple stripes with uniform spacing.  I shoot the stripes with an airbrush and then clearcoat them to protect them from wear. 

Photos of two bikes I used the tape on.

Every once in a while you'll find a Sprint, Pichler, or other european aftermarket K bike fairing. Interesting thing is that those fairings worked better than the factory.

They were fun builds..wish I had kept the K76 (K75 with a K1 tranny back). That bike moved and comfortable for 700 mile days.

One built with a Sprint fairing

I almost bought a  Sprint Fairing, but I find it's not sporty enough and too round shaped to fit the k lines.

And one built with a Pichler PK2 fairing..VERY comfortable and fast machine.

Yes, I like more the Pichler. Especially with the full fairing...


A few years ago, I missed such a Pichler K100, 2km from home for 300€...the selle asked me to call back later as he was busy that week end, and when I called sunday evening, it was already sold.

What's new?

A set of nice PVM rims.. 
After a long search, I eventually purchased these aftermarket wheels dedicated to the K100.
New tyres, new bearings, recently resprayed...all good. Even the center cap is there, with a special holder. There are no centering cones on rear rim.



These rims are sand casted in aluminium (no magnesium, I would not dare riding on 40 years old magnesium rims!), with empty spokes.  
The weight is slightly lower than the 3 spokes sport BMW rims, so its probably the same as the 4 Y spokes. 
But I frankly prefer their shape, they look like sharpened polished con rods, whereas the sport BMW rims are poorly finished on the right side, smooth only on the left side.
 


Curiously, on the front rim, each disc is bolted on the hub, withou nut. I could not reuse the common long screws that links the both discs on the BMW rim.


The size is the same as the genuine rims. I don't want big tyres, unecessary and nocive for maneuvrability.
 


Last but not least, the final show off touch: clear blinker lenses. 
Absolutely useless, but consistent with the "aftermarket accessories shelf" concept of this bike!



Next steps to come: a pair of Brembo P09 calipers with  48mm pistons, a fiberglass light fairing...and the  Luftmeister performance engine parts. :clin:

Sharp. Very nice. I like your "connecting rod" image. Thanks for keeping us up-to-date on your "build" - I flinch when I use that word because it so often used where it should not have been used.

Cheers.

jbt wrote:PVM rims.. 

These rims are sand casted in aluminium (no magnesium, I would not dare riding on 40 years old magnesium rims!), with empty spokes. 

jbt, mes félicitations!


A good friend of mine who has kept my Eco running since 2009 and who certainly does know his stuff strongly advised me to keep the Alumin(i)um PVM front wheel and never even think of changing to the lighter Magnesium wheel. Ever.

Why?
a) the Mg PVM wheels were built and sold 'for racing only' - so they are not street legal
b) he has seen tons of those in the last decades - all of them cracked, every single one. FUBAR

I found last week a pair of very rare BERINGER brake calipers, dedicated to K75 & K100, that I'm fitting on this racer;


These calipers are made in France, they use separate pads for each pistons. They are known to give a very powerful  braking.

I'm waiting new brake lines to test it.

The OEM brake disc looks very small with these calipers. But...I have something to correct that.
Last year, I spotted an appealing K100RS for parts on a local ads website, the french equivalent of Craigslist;
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The black and red color of the bike on the thumbnail teased me: it looked like the K100RS Turbo of Arcueil Motors, the french distributor of the Luftmeister Turbo kits:


Was it my Graal? The rear boot showed a sticker Arcueil motor.: 




Actually, not. It just was a mockup of the real turboed K100RS. But if it had no turbo, it had an interesting feature: a BREMBO 300 mm cast iron brake discs kit, with adapters for the calipers.





SEMC was the french distributor of BREMBO products in the eighties. Rovering into old catalogs and magazines, I had seen that this reference for K100 had existed, but never saw this kit. 
Naturally, I bought them immediatly!
The hubs are OK but the rotors are corroded. It's normal with cast iron. But the plates also are corroded, and I'm looking for someone that could machine new ones for me. 
Then Ill mix them with the BERINGER calipers...

Beringer was a sidecar builder in the eighties and began in 1990 to produce cast iron brakes to challenge BREMBO products. Then, he stopped sidecars to product high quality brakes.

How DO you find such rare gems!? It would be wonderful to be able to obtain any and all of these now-ancient parts so they aren't lost to time.

Well, that's simple: I'm searching.
On the net, but there are few opportunities.
In the real world, where there are much more common.
I attend a lot of swap meets, particularly the Veterama in Manheim where a lot of BMW parts are waiting. 
But in spite of the huge amount of parts there I found unique parts in the local vintage bikes swap meet (the Fallert seat and the rearset).

I must be gifted to find BMW parts.

2 weeks ago, I also had an encounter with a guy that was one of the very first man to ride a K100 during the summer of 1982 on road for secret road tests in France... but that will be another topic, when I'll get all the pictures from him!

Of course, keeping one's eyes open is what turns them up. Here, where there's is a preponderance of swap meets, often it's row upon row of rusted Harley pieces with a smattering of vintage Japanese parts & British spares. Rarely does one find an old Lufty pipe or interesting aftemarket Beemer piece. They're out there, but the US, despite its size, was never the beating heart of go fast/stop fast goodies for BMW as in Europe.

Last October, at the Barber Vintage Festival and combined BMW Motorrad 100 year (well-attended) gathering, were only two tables of K bike parts, mostly overvalued junk. Nothing any enthusiast wouldn't already have on their garage shelf.