The Doppler offers riders a traditional brevet and touring bike with smooth-rolling 650B tires that can venture into the dirt for those off-road excursions.  While gravel riding is the latest trend, 650b wheels have been a well-kept secret within the brevet community for decades! 650b offers a distinct advantage by offering a larger-volume tire to provide both greater cushion and traction on rough roads. The smaller- diameter 650b rims also provide a stronger wheel which is ideal for loaded touring or harsh conditions. Compared to the Inversion and Radar the Doppler frame offers a more classic road bike geometry while still offering a high level of functionality with a wide-range drivetrain and frame features.