Reborn: “Flacheisen” (Flat Iron) from Radical Speedshop…
For nearly 30 years, the Bronold family of Germany’s Radical Speedshop has been building, customizing, and racing Moto Guzzi machines. Truly, you can hardly speak of Guzzi performance without their names coming up.
We’ve had the honor of featuring several of their radical Guzzi builds, including their nitrous-injected drag bikes — “NOSferatu” and “NOSferatwo” — as well as their 1700cc “Cento Anni” café racer, which they also race.

Today, we’re thrilled to feature their new build — one that harks back to the earliest days of the workshop.
“Flacheisen [Flat Iron] was our first build in 1996 and we wanted to build a new Flacheisen with all the know-how we’ve gained from over 27 years of Guzzi customizing.” -Stefan Bronold
Nicknamed the “Flacheisen S,” the bike began life as a 2001 California 1100, but little of the original donor remains. The frame is from a Le Mans III, while the transverse V-twin shaftie comes courtesy of a mid-2000s Guzzi V11 — outfitted with hotter cams, Keihin FCR 41 carb, and one-off stainless underseat exhaust for a power output north of 100 hp.
Other highlights include upside-down forks with CNC-cut triples, spoke wheels with a 180 section rear tire, Brembo four-piston brakes, 1100 Sport tank, alloy tail section with alcantara saddle, and more.
As intended, the upgrades have completely transformed this Guzzi from a staid old Italian roadster into something truly special:
“It has the style of a café racer but the suspension and engine make it perform like a new bike.”
Stefan says they’re proudest of the stainless underseat exhaust system, which took more than two weeks to build and manages to snake through the swingarm at one point — trick!
Below, we talk to Stefan Bronold of Radical Speedshop for more details on the “Flacheisen S.”
Moto Guzzi 1100 Café Racer: Builder Interview
• What’s the make, model, and year of the donor bike?
Moto Guzzi California 1100 I.E.2001
• Why was this bike built?
Promotion bike for our showroom.
• What was the design concept and what influenced the build?
Flacheisen was our first build in 1996 and we wanted to build a new Flacheisen with all the know-how we’ve gained from over 27 years of Guzzi customizing.
• What custom work was done to the bike?
- Upside down fork with CNC triple trees
- Spoke wheels with 180 rear tire
- Brembo four-piston brakes
- 1100 Sport tank
- Alloy tail
- Stainless underseat exhaust system
- Engine from a V11 with upgraded cams, etc. to have 100 hp
- Alcantara Seat
- Steel effect airbrush
- Frame from a LM3
- Keihin FCR 41
• Does the bike have a nickname?
“Flacheisen S.”
• Can you tell us what it’s like to ride this Guzzi?
It’s a modern cafe racer. It has the style of a cafe racer but the suspension and engine make it perform like a new bike.
• Was there anything done during this build that you are particularly proud of?
The exhaust system was really crazy to build and took two weeks. The underseat side goes through the swingarm where there’s not much space.
Follow the Builder
Website: www.radicalspeedshop.com
Facebook: @radicalspeedshop
Instagram: @radicalspeedshop
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Moto Guzzi bikes are nice but mostly cruisers.
Not too exciting and good cop bikes but…
This is beyond that and nice, Very nice
Gorgeous.
The motorcycles that you feature in the magazine are over the top beautiful creations. I get hundreds of emails everyday but I always take time, no matter how busy I am to red the articles you send. Thanks for an inspirational publication!
How can it be a 2001 California when it has a different engine, frame & tank among other things?