From Open Source LongTail Technology
Xtracycle LongTail Standard - Open Source information
The bicycle industry is entering a new age of bike design. Changing culture and rising costs of resources are getting more people onto bikes, many of which are used for commuting, hauling groceries, or good old off-road fun. Xtracycle has been building the Free Radical kit for about 10 years, with other manufacturers such as Surly jumping on the bandwagon to create one-piece frames. Smaller fabricators are making their own bikes, and the demand for an open-source standard is increasing.
Xtracycle has therefore decided to put the basics of their Longtail design up for anyone to use. While we want to ensure the compatability of parts, we’re not charging money for the right to use our technology. We only ask that makers conform to a certain set of criteria, so that customers can be assured that everything will work well together.
Established Frame Standards
The two most important documents for framebuilders:
These pages explain the existing dimensions, and are intended to provide designers with deeper explanation of why things are the way they are, and what problems have been encountered before. For the authoritative dimensions and requirements, always refer to the LongTail Frame Standard and the Longtail Dimensions pages. This is a PDF that contains all of the details relevant to the frame of a longtail bike. It repeats much of the information below. For the final word, refer to the PDF.
- Terminology and Anatomy of the Free Radical
- H-rack Locations
- V-rack Locations
- Size of tubing
- Keep-out spaces for accessories
- Disc Brake Mount
- Rohloff mount
- Dropout direction
- Derailleur hanger
- Fender Mount
- Freeloader Strap Mounts
- Cantilever Stiffening
- Kickstand Plate
- Adventure Kit
Projects designed to be completed, with relative ease, at home, on your own, but we highly suggest having a friend help, hence, Do-It-Together.
A place for designers to discuss what should be made, and how. When creating new subjects, try to use the need that's being addressed, instead of the particular product. Make sure you delineate between what's a discussion and what's solid information. Also, remember that while Xtracycle isn't here to steal your ideas, anything you put on here is now open-source and as such is available for everyone to use freely.
- 2/3-Kid Carrier
- 29er compatible Longtail
- Mobile Pet Salon
- Propaganda holder
- Small dog carrier - specifically French Bulldogs
- 20"/Folding bike compatible Longtail
Please visit the Community Portal to share your custom designs, mods and ideas with other Xtracyclers.