Light tubing, up to 55mm tires, adventure-ready geometry, the Purple Haze is the workhorse at Sour.

Explore your world on a whole new level. The Purple Haze, with it’s huge tires, light steel frame, and quick handling is the bike to truly get lost on all the asphalt, gravel, and even singletracks you can find. The first and oldest platform from Sour Bicycles, the Purple Haze stands the test of time.

The Purple Haze is the go-anywhere do-anything big gravel bike. With its up to 55mm knobby tire clearance, the Purple Haze is geared up for any adventure you can dream up. With a good balance of agile geometry and all day comfort, this frame is the mainstay for all sorts of gravel riding.

The Sour Purple Haze has seen the world. Riders take this frame all over the world on all sorts of adventures. This frame is fast and chill, quick and stable, and like a best friend, its always got your back.

Adventures big or small, the Purple Haze is ready to roll.

This platform was one of the original three bikes Sour designed when Sour was still a skunkworks, and when they designed the Purple Haze, it was perfect from day one.

Since those days, Sour Bicycles refined the platform and updated it as needed. Nowadays the Purple Haze has a yoke to better support its big tire addiction, but the geometry and soul of this bike has stayed true to its very first kilometers.

Get yoke’d, not yolked.

When Sour were designing the current generation of the Purple Haze, they really wanted to push the tire clearance to safely fit up to 55mm tires. Now, not all tire and rim combinations were created equally, so your results may vary, but in general, the yoke allows the space to run straight-up mountain bike tires on the Purple Haze.

Sour designed the Purple Haze yoke in-house to achieve the design goals they wanted, but also to make welding easier to support their own in-house frame production.

Details of the Sour Bicycles Purple Haze Frameset

Purple Haze frame

• Sour Bicycles frames are made by hand, one-by-one, in their own facility in Saxony, just outside of Dresden
• Custom tubing designed and drawn for the frames, it’s a multi-butted heat-treated 4130 CrMo steel that’s ready to stand the test of time
• Steel is produced from a partially recycled product in Germany and drawn by one of the worlds leading production facilities in Taiwan
• Dropouts are designed in-house in Dresden and have a replaceable derailleur hanger
• The seat clamp is designed in-house and is integrated into the frame. Should it ever fail, the frame can be professionally modified to use a traditional clamp, if repair of the original clamp is not possible. Sour has never seen one fail
• Headtube: 44 mm upper and lower
• Bottom bracket: 68mm T47 threaded bottom bracket
• Thru-axle: 12 x 142mm thru axle
• Seat post: 27.2mm
• Brake standard: Flat Mount FM160 Direct
• Wheel size: Size XS/S 650B optimized (bb height), Size M – XXL fit 700C/29“
• Tire clearance: up to 55mm
• UDH/Transmission Compatible
• Fender and rack mounts
• Recommended tire size 45mm – 55mm
• Two water bottle mounts inside frame, third bottle mount under downtube
• External cable routing on the downtube for mechanical drivetrains
• Internal brake hose routing

Business Carbon fork

The Business Fork is the Sour Bicycles carbon gravel and adventure fork designed for all the adventures, big and small!

It is designed in-house and worked with the Sour long-term production partner in Taiwan to make it. Sour have tested this fork at EFBE in Germany and pass their Tri-Test with flying colors!

• Material: UD Carbon
• Maximum Tire Width: 55mm
• Axle to Crown Length: 403mm
• 45mm Rake
• Tapered Steerer Tube 1½” – 1⅛”
• Thru-axle: 12 x 100mm
• 3 Cargo Cage Eyelets on Fork Legs
• Internal Dynamo Cable Routing
• Flat Mount Brake Mount 160mm
• Fender Mounting Possible
• Weight with full length steerer and thru axle: ±565g
• Brake mount thickness: 35mm

Included with your frameset

• Purple Haze frame & Business Carbon fork
• All the grommets and small parts to run any cabling you wish and a derailleur hanger
• Rear thru-axle
• Front thru-axle