Compass Bicycles is introducing our new Compass 26″ x 1.75″ tires (42 – 559 mm). Many readers and customers have asked for a 26″ version of the much-loved Grand Bois Hetre 650B tires. This would allow riders of mountain bikes, touring bikes, tandems and small frames to enjoy the speed and comfort of wide tires with supple sidewalls.
The Compass 26″ has the same casing construction and tread thickness as the Grand Bois Hetre. At 42 mm wide, the Compass 26″ tires are are a few millimeters wider than the Hetre (40 – 584 mm), and they fit smaller 26″ (559 mm) rims.
Panaracer makes the Compass tires for us. (They also make Grand Bois tires.) Panaracer’s Pasela uses the same mold as the Compass 26″ tires, but the Compass tire uses a different casing construction. The result is lower rolling resistance and a more comfortable ride. The tread rubber is different, too, offering better grip. Finally, the tread may be a little thinner, while still offering long life. The Compass tires use a folding Kevlar bead.
While the Pasela is a budget tire that offers very good performance for the money, the Compass is a high-end tire optimized for performance and comfort.
Wide 26″ tires do make a lot of sense. When we tested wheel sizes and bicycle handling for Bicycle Quarterly (Vol. 8, No. 3), we found that gyroscopic forces determines stability while cornering. To keep the gyroscopic forces the same when you want wider tire, the wheel should be smaller in diameter. Conversely, narrower tires handle best with larger wheel diameters.
In that study, we concluded that 700C wheel diameter is best for tires up to 32 mm width, 650B wheel diameter is best for tire widths between 35 and 42 mm, and even wider tires should use 26″ diameter rims. (Other riders may prefer different handling characteristics, and hence their wheel size preferences may be slightly different.)
Grand Bois offers 700C and 650B tires in the “optimal” sizes. However, no manufacturer was producing fast, supple, wide tires for 26″ rims. So we worked with Panaracer to develop the Compass 26″ tires. The new tires use existing tire molds, and they are made with the highest-quality casings and materials, like the Grand Bois tires. The result is a tire with excellent comfort and speed, and superior grip on dry and wet pavement.
I envision numerous applications for these tires. Many existing mountain bikes and tandems can be transformed with supple, fast and comfortable tires. Small frames can be designed for these tires with fewer compromises, while maintaining the stability of a large-wheeled bike. In addition to optimizing the handling, the smaller wheels make it easier to fit a wider tire between the chainstays. A bike designed for 26″ wheels could be used with the Compass 26″ tires on paved and gravel roads, and with knobbies in more technical terrain.
26″ tires also are ideal for bicycle tourists planning extended trips to foreign countries, where 26″ tires are most commonly available. On a round-the-world tour, you can enjoy the comfort and speed of these high-end tires. If a tire must be replaced prematurely, 26″ tires are the most common size used today around the globe.
Here are the specs for these tires:
- Width: 40-42 mm
- Weight: 440 g
- Thickness (tread + casing): 3.8 mm
- folding bead
- Price: $ 60
The new tires are available from Compass Bicycles and many bike shops. In addition, Compass Bicycles now also sells the Pacenti Pari-Moto tires, which are wonderful event tires in 38-584 mm (650B).
- Wheel Size and Bicycle Handling. Bicycle Quarterly Vol. 8, No. 3, p. 14.
- Gyroscopic Forces and Optimum Wheel Sizes. Bicycle Quarterly Vol. 8, No. 3, p. 19.