A First Flat Tracker from Workshop43…
Yamaha’s 500cc singles are some of the most versatile motorcycles ever built. The XT500 became a darling of the off-road world, taking home trophies in the big African rallies and remaining a favorite of vintage enduro enthusiasts around the world to this day. Meanwhile, the SR400 and SR500 street bikes gained something of a cult following over the years for their simplicity, reliability, and the charismatic “thump” of their single big pistons.
Our buddy Andreas — aka “Andi” — of Germany’s Workshop43 has quite the affinity for these Yamaha singles. His previous SR500 build made our list of the Top 10 Scramblers of 2024, while his XT500 restomod remains one of the most popular Yamaha singles we’ve ever featured.
Back in 2023, Andi participated in his first flat track event, and he absolutely loved it — especially the bikes and community.
“I’m not a particularly skilled rider, but the event, its unique atmosphere, and the great people I met there inspired me to give flat track racing a try. For me, it’s less about the riding and more about building the bikes. My goal was to have a finished bike ready for the next race in 2024 and compete.”
Andi is one of those guys who always has a project going, and he’s not scared of a challenge. Growing up, he built everything from an engine-powered pedal car to tuned 50cc scooters to a 100-hp Honda CBR-powered gokart! So it only made sense that he would built his own flat tracker.
The SR500 and other single-cylinder four-stroke engines have long been popular in flat track, as their relatively flat torque curve and friendly power delivery make them well-suited to finding traction on a dirt track. Andi scored a ’78 SR500 engine and frame from the same buyer, and using a bunch of parts left from previous projects, he set out to build his first flat tracker from scratch.
He let the lovely patina of an old red and white tank serve as the aesthetic foundation of the build, and got to work building the bike from the frame up. Up front, he didn’t just fit a set of Kawasaki ZX-6R forks and a steering damper, but also steepened the steering head angle for quicker turning — a substantial modification we rarely see on an OEM-framed tracker:
“I’m particularly proud of modifying the steering head angle, something that isn’t allowed on street motorcycles in Germany. This race bike gave me the perfect opportunity to test it out. To make it happen, I had to build a frame jig beforehand, which was a new experience for me.”
The detabbed, shortened, and steepened frame was painted a red that really pops against the white bodywork. Out back, Andi mounted a KTM wheel with a modified XS750 brake, sewed up the seat himself, and made the side and front number plates.
The engine was completely rebuilt with a bigger oil pump, better oil routing to the rocker arms, new valve seats with stronger springs, and more. It wasn’t tuned for big power, as Andi is the first to admit that he’s a novice on the track.
Though the original race he’d scheduled to participate in was canceled, Andi ended up running the bike at Flatland360, hauling it there on the back of his Defender 110 — what a setup!
He had a blast at the event, met a lot of great folks, and the SR500 proved itself a perfect flat-tracking companion:
“Riding this bike on the track and carving through the left-hand turn was incredibly fun. The modified steering head angle and the wide steering lock make the bike very agile. The sound is amazing, and overall, I’m really happy with it and have a lot of fun riding it.”
Andi is one of the best builders around when it comes to recording his progress in the workshop, and we highly recommend you subscribe to his YouTube channel Workshop43 to follow along with his projects.
Below is our full interview about this SR500 flat tracker along with more gorgeous shots courtesy of Andi’s brother, Stefan Wanning (stefanwanning.com). Here’s to a 2025 full of loud thumpers and left turns!
SR500 Flat Tracker: Builder Interview
• What’s the make, model, and year of the donor bike?
The foundation of my project is a 1978 Yamaha SR500 frame paired with an SR500 engine. There wasn’t a donor bike in the traditional sense, as I started with individual parts. I had leftover engine components from previous XT500 and SR500 projects and decided that an SR500 engine would be the perfect starting point.
When I purchased the engine at a bargain, the seller also gave me an SR500 frame for free. The frame was already partially cut, making it an ideal base for my project without sacrificing a functioning frame. With this combination, I built the bike entirely from scratch.
• Why was this bike built?
In 2023, I participated in a flat track event as a complete newbie – riding my Honda CB250, which was just my daily commuter and far from being a race bike. I’m not a particularly skilled rider, but the event, its unique atmosphere, and the great people I met there inspired me to give flat track racing a try. For me, it’s less about the riding and more about building the bikes.
My goal was to have a finished bike ready for the next race in 2024 and compete. Unfortunately, the race was canceled due to organizational issues. Instead, I had the amazing opportunity to participate in Flatland360, which was an incredible experience – both the event itself and the community there were absolutely fantastic!
• What was the design concept and what influenced the build?
The design concept was simple and stripped down to the essentials – classic, straightforward, and exactly how I like it. Since I built the bike solely for myself, my standard is always that it should look good enough to serve as decoration in the living room (currently, my Suzuki GS550 holds that spot, maybe I have to switch now).
The tank, with its beautiful patina, set the tone for the red frame color. Everything else came together organically during the build. Usually, I start with a vague image of a bike in my mind, which becomes clearer as the build progresses. So, the bikes essentially develop themselves during the process.
• What custom work was done to the bike?
The bike was completely rebuilt from the ground up, starting with a bare frame. Here are the key customizations:
• Fork: A fork from a Kawasaki ZX6R, just like on my other SR500. It’s sturdy, affordable, and perfect for my needs. The brake mounts were removed since front brakes aren’t allowed.
• Frame: The steering head angle was made steeper, the frame was shortened, and all unnecessary brackets were removed.
• Rear Wheel: The rear wheel is from a KTM. The rear brake comes from an XS750 but was shortened.
• Seat: I sewed the seat myself using Alcantara.
• Engine: The engine was completely rebuilt and wet-blasted to ensure it’s clean and visually appealing. Upgrades include a larger oil pump, modified oil routing in the head to the rocker arms, stronger valve springs, and new valve seats. There’s also an open air filter and a larger carburetor jet.
• Custom spokes from WWS
• Additional Modifications: A steering damper was installed.
• Self made number plates
The bike is essentially a colorful mix of parts. The best way to see all the modifications and details is by checking out my video series on YouTube and Instagram (@Workshop43).
• Does the bike have a nickname?
No, my bikes and cars never have nicknames 😊
• Any idea of horsepower, weight, and/or performance numbers?
The engine wasn’t heavily tuned; it was mainly refreshed and made reliable. Since I’m not a very skilled rider, I don’t need extreme power. Maybe I’ll consider tuning it if I get better. I haven’t measured the weight yet, but the bike is very light since there’s hardly anything left on it. It would be interesting to measure it at some point.
• Can you tell us what it’s like to ride this bike?
I don’t have many points of comparison, but riding this bike on the track and carving through the left-hand turn was incredibly fun. The modified steering head angle and the wide steering lock make the bike very agile. The sound is amazing, and overall, I’m really happy with it and have a lot of fun riding it. The power is more than sufficient as well. That said, I’m no flat track expert, so this is just my perspective as a beginner.
• Was there anything done during this build that you are particularly proud of?
I’m particularly proud of modifying the steering head angle, something that isn’t allowed on street motorcycles in Germany. This race bike gave me the perfect opportunity to test it out. To make it happen, I had to build a frame jig beforehand, which was a new experience for me.
Beyond that, there were plenty of small challenges during the build that were really enjoyable to tackle. However, I didn’t try anything overly extravagant with this bike since it’s meant to be a race machine that performs well rather than a showpiece with unnecessary visual extras.
• Is there anyone you’d like to thank?
I’d like to thank a few people and companies who supported me during this project:
• Kedo, for their help with parts – they truly have everything you could need for Yamaha
• Everyone on YouTube and Instagram who shared tips and supported me throughout the build.
• The awesome people at the flat track events who inspired me to get into flat track racing.
• My brother for always taking perfect photos.
• And, of course, my wife for letting me spend so much time in the workshop. 😊
Follow the Builder
• Instagram: @Workshop.43 – Here, you can find additional photos from the build process and updates on everything else happening in my workshop.
• YouTube: Workshop43 – On YouTube, you can watch the full build series. Don’t forget to subscribe to the channel to stay updated on new projects and releases. I appreciate all the support!
• Photographer: The photos were taken by my brother (www.stefanwanning.com)
Nice!
Very clean build but why not paint the tank?