Oldschool Classics builds the perfect backroad burner…
The BMW R100RS was Motorrad’s 980cc sport-tourer, built around a 70-hp version of the two-valve flat-twin boxer engine. Even in its heyday, the Bavarian boxer wasn’t as fast as the Japanese sport machines, but it would cruise forever at 100 mph and was extremely surefooted at speed…both in the turns and on your local freeway.
“It wasn’t the arm-wrenching acceleration of a 900 Kawasaki, or the frenetic wheelie-popping surge of some of the quick two strokes, but at every bend, or every time I checked the speedo, I found I was traveling much faster than I thought.” -Motorcycle, 1977
Yes, the R100RS could make any highway into an Autobahn, if you could afford the tickets. And with a 5-gallon tank and 50 mpg fuel economy, you could ride for hours without worrying about fuel stops.
Enter our new friend Bernhard Adelsberger of Austria’s Oldschool Classics, who rebuilds and customizes vintage motorcycles and antique wooden boats out of his small workshop outside Salzburg. The area is known for both rolling plains and the northern boundary of the Alps, making for some incredible roads. Bernhard wanted to build a bike perfect for his native countryside.
“My vision was to build a classy scrambler for riding old dusty farmland roads in the region of Upper Austria, where I live. In this part of Europe you can find empty lanes winding through forests and fields. So I wanted to build a bike that’s pretty fast, handles well, is quite comfortable, and has decent off-road abilities when needed.”
The donor is an ’82 R100RS, which had been gathering dust in the back of his workshop for years. The time had finally come to breathe new life into the old workhorse. The bike would need to be stable at speed, good in the curves, have plenty of punch for its intended use, and have the ability to leave the tarmac when adventure struck.
Bernhard has included a full build sheet below, but highlights include a rebuilt engine, YSS rear shocks and Wilburs progressive front springs, Walzwerk subframe and seat, handmade aluminum fenders, custom wiring harness with Motogadget / Motone / Kellermann e-goodies, Hattech stainless silencers, and some neat extras like the ebony wood fork inlays and a vintage Riva (antique wooden boat) charge control lamp.
The headlight is from a 70s Yamaha DT and the handlebars from an XT500. We especially love the tank, which Bernhard designed to imitate an old “Werks Team” bike with original patina. Getting the bike’s lines just right was crucial Bernhard, who says he must’ve fit and removed certain parts a hundred times to strike the right balance.
The bike looks great, but it was built to ride…and there it excels.
“A fast vintage bike which is fun for countryside cruising. The improved chassis is very stable in higher speeds but still dynamic with its low gravity point and raised handlebar. The knobby tyres do not slip on dirty asphalt and short off-road sections are fun. The stainless steel pipes sound like rock music in your ears. What a cool bike to ride!”
Bravo, Bernhard! You’ve got the perfect flat-twin backroad burner on your hands…and we’re jealous of the roads you have in your part of the world. Please enjoy this boxer for the rest of us!
Below you’ll find our full interview with Bernhard, along with more details about the project and a full build sheet of everything done to the machine.
R100RS Scrambler: Builder Interview
• Please tell us a bit about yourself, your history with motorcycles, and your workshop.
My name is Bernhard, I am 48 yo and I live on the countryside near Salzburg / Austria EU. I have been tinkering on bikes and other stuff since I can think. Always loved getting my hands dirty and taking everything apart and creating something to ride.
When I was young I customized vintage bicycles and restored and tuned old Vespas. Later I started a business named OLDSCHOOL CLASSICS and built my own little workshop. Now I am restoring and customizing vintage motorcycles and antique wooden boats.
My favourite bikes are vintage Yamaha 500 (SR, TT, XT), BMW 2V Boxers, and vintage Triumphs. The BMW R100 RS Scrambler was finished in 2024. My latest project is a 1969 Triumph Tiger Desert Sled.
The budget is always rather small and I try to reuse or adapt old used stuff for my builds. One of the coolest things is to give a bike a new life and then ride it in the beautiful countryside. I am mostly working alone or with a helping hand from a gasoline addicted friend. I have a good network of professionals for different things.
• What was the design concept and what influenced the build?
My vision was to build a classy scrambler for riding old dusty farmland roads in the region of Upper Austria, where I live. In this part of Europe you can find empty lanes winding through forests and fields. So I wanted to build a bike that’s pretty fast, handles well, is quite comfortable, and has decent off-road abilities when needed.
As a vintage guy the choice fell on the big aircooled boxer from Bavaria / Germany. An old reliable working horse with simple technics, still one of the fastest bikes back in the day. I had it sitting in the back of my workshop for some years, waiting for the right chance. So it was about time to pull it out, strip it, and give it a new life.
The BMW Scrambler turned out great with its classy tank design and proved to be a fast vintage bike which is fun for countryside cruising. The improved chassis is very stable in higher speeds but still dynamic with its low gravity point and raised handlebar. The knobby tyres do not slip on dirty asphalt and short off-road sections are fun. The stainless steel pipes sound like rock music in your ears. What a cool bike to ride!
• Was there anything done during this build that you are particularly proud of?
With the BMW R100RS I tried to achieve a clean, light weight, and classic look. I loved doing my own tank design imitating an old WERKS TEAM bike with original patina. I guess it came out great and fits perfectly in my design concept.
The bike is fully street legal, which was not easy without doing compromises in design – in particular here in Europe.
Also the lines of the aluminium fenders, especially rear fender came out nicely. A big difficulty always is to get fender angle, taillight, license, plate and suspension clearance in perfect alignment. After taking the fender on and off 100 times I finally like the result.
• Is there anyone you’d like to thank?
I would like to thank my friends to always pushing my motivation and inspiring me. There is nothing better than philosophizing about motorcycles with my homie Mike over some cold beers. I also thank my wife for her patience, love and support. Finally I thank myself for never giving up.
Full Build Sheet
*BACK COUNTRY SHREDDER: BMW R100 RS from 1982*
BUILT BY:
=========
Bernhard Adelsberger
OLDSCHOOL CLASSICS
Salzburg, Austria
www.oldschool-classics.at/bikes_cars
Engine:
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+ original 980cc boxer, restored
+ 70 HP at 7250 rpm
+ original Bing 40 carbs, rebuilt, synced, painted black dots
+ air filter case and top cover changed to old version for better look
+ ignition restored with new NGK cables and plugs
+ engine protector bracket, original BMW RS, polished
+ exhaust, custom stainless mufflers from Hattech, original manifold
+ model emblem removed
+ custom painting, 100
+ electric starter
Frame, Chassis, Seat, Tank:
==========================
+ rear suspension YSS-RZ362-TRL-A, 400mm, alloy black
+ front fork progressive Wilbers springs
+ rear frame, Walzwerk
+ custom leather seat, Walzwerk
+ original brembo disc brakes, rebuilt
+ all cable lines new with teflon
+ handlebar, Tomasselli Enduro with original BMW controls, restored
+ original R100 gas tank, designed and painted in classic style with O.C. logo
+ aluminium fenders, custom made
+ licence plate holder, custom made
Tyres:
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+ front Continental TKC 80 Twinduro 100/90-19
+ rear Continental TKC 80 Twinduro 4.0-18
Electric:
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+ complete new minimal custom cable harness
+ vintage front light from Yamaha DT250 with grill, Tomasselli mounts
+ backlight from Motone Eldorado Aluminium cast, LED
+ blinkers Motogadget m-blaze with Kellermann relay
+ lithium battery in bottom case, beside gearbox
+ fiamma horn
+ ignition key, built in motor case
+ vintage Riva boat charge control lamp
Xtras:
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+ vintage fog light yellow, Hella
+ mirror, Biltwell
+ front fork wood inlays, custom made of ebony
Follow the Builder
OLDSCHOOL CLASSICS
Bernhard Adelsberger
Austria / European Union
www.oldschoolclassics.at
Instagram: @oldschool__classics
For me, it’s one of the most balanced and therefore most appealing Airheads I’ve seen in recent years. Respect for the excellent craftsmanship, the matching paint job, and the minimalist yet practical design. Cheers from Berlin.