Sour Purple Pie and Purple Haze: Steel gravel bikes with the option of a derailleur and 32" wheels

Anyone in Germany with an interest in gravel bikes with steel frames will, sooner or later, come across the Sour brand. The Dresden-based company has two model ranges in its portfolio, both of which feature locally manufactured steel frames and offer versatile build options. Sour also caters to unusual customer requests and brings extraordinary custom builds to life. We took a closer look at two of these and came across some details well worth seeing.

Conclusion

Sour’s steel-framed gravel bikes are available from very reasonable prices. The sleek lines of the steel tubes are always a real eye-catcher. Anyone wishing to build themselves an exclusive gem ‘made in Germany’ will probably need to invest a little more. Gear systems, custom paint finishes, special requests: at Sour, almost any dream can come true. - Jan Timmermann, TOUR editor

Dream gravel bikes from Germany

Sour Bikes takes the approach of developing bicycles based on specific requirements and its own vision of cycling. The brand relies on steel frames, an in-house design process and manufacturing in its own workshop in Saxony. Durability, repairability and the option for customisation play a key role in this. All frames are crafted from multi-butted, partially heat-treated CrMo steel tubes. Sour’s philosophy combines traditional frame-building craftsmanship with a commitment to tailoring geometry, materials and components to the specific intended use. In-house production also enables Sour to easily produce bespoke designs – from an additional mounting point to an oversized frame. Custom paint finishes and builds appeal to the individualists amongst gravel cyclists. Despite being manufactured in Germany, the prices for the gravel bike frames remain relatively low.

Classic Steel: Sour Purple Haze

The Purple Haze is Sour’s most popular model and is defined as a classic steel gravel bike for everyday use and all kinds of riding. The Purple Pie does not want to be pigeonholed into a single gravel bike category. Compared to the Purple Pie, however, its focus is more on sporty riding. Nevertheless, the frameset allows for the fitting of mudguards and a luggage rack. The frame accommodates gravel tyres up to 55 millimetres wide. A UDH derailleur hanger allows the use of SRAM rear derailleurs with the Transmission standard. DIY enthusiasts will appreciate the bolted T47 bottom bracket and external cable routing. The frame, weighing around 2,195 grams, retails for 1,299 euros. A matching steel fork can be ordered for 249 euros. A carbon fork is available for 349 euros.

Sour has finished the custom build for the Bespoked trade fair in dark purple to match the name ‘Purple Haze’, complementing it with shiny silver components such as the stunning Raketa chainring. A SRAM Red XPLR AXS drivetrain and carbon wheelsets keep the weight of this high-end gravel bike down. Sour has also fitted a front rack for carrying luggage and a lighting system with fully integrated cable routing.

Worry-free thanks to the gear system: Sour Purple Pie

Sour offers its gravel bike with a Pinion gearbox under the name Purple Pie. The bike is specifically designed for adventurous routes through the countryside and is the choice of many bikepackers. The Purple Pie also accommodates tyres up to 55 millimetres wide. The main difference compared to the Purple Haze lies in the low-maintenance gear system. To achieve this, Sour uses special, horizontally adjustable dropouts, which allow the drivetrain to be tensioned. Prices for the frame, including the gear system, start at 3,499 euros. The Purple Pie can be ordered with the same forks as the Purple Haze. Sour states the frame weight as 2,795 grams in size Medium.

​Sour has built a bespoke version of the Purple Pie for a customer over two metres tall. Based on standard frame sizes, this one-off bike would be roughly equivalent to size XXXXL. To match the frame’s massive proportions, 32-inch carbon wheels from Nextie have been fitted. This could be a glimpse into the future: will we soon be seeing production gravel bikes from Sour featuring this new wheel size? For now, this question must remain unanswered; Sour already offers mountain bike frames for 32-inch wheels. Power is transmitted via a Gates belt on the show bike. A hub dynamo supplies power to the lighting system. Visually, the steel frame makes a statement with an eye-catching, two-tone custom paint finish.

What do you think: would you be interested in a gravel bike with a steel frame, or do you prefer carbon? Let us know in the comments!