700c, 27-Inch & 650c

BOS is the airport code for Boston, Massachusetts, the original hotbed of North American ‘cross and home to some of the harshest weather and the toughest courses. If you’re pinning on a number in New England you better be ready for rain, roots, ruts and mud. And, you better have a set of Donnelly BOS tubulars in your quiver. This tire is even more aggressive than our mud-proven PDX. It features buttressed side-knobs for outstanding traction in super muddy corners and off-cambers, and a center tread pattern that is all bite when it comes down to a tractor pull. Size: - 700 x 33mm Weight: - 386 grams Type: - Tubular Part #: - D50030 Product Features: - Buttressed side-knobs for superior cornering traction. - Unique center knob pattern designed for maximum traction when you need it most. - Soft rubber compound provides extra grip and shock absorption. - Tubeless design means an airtight casing with no inner tube to puncture. - Rubber-coated sidewalls are extremely durable and prevent deterioration from water, mud and dirt. - No additional sidewall coating necessary. - All in one construction means tread will not peel away from the tubular casing. - Precision design creates a straight tire with no variances in size or alignment. - The tire and base tape are consistently straight making it easy to glue and install to your wheel. - A removable valve core allows for valve extenders installation as well as insertion of tire sealant. - Liquid sealant can be used with all Donnelly tubulars to prevent or repair typical punctures.

Kenda Street K40 Tire - 27 x 1 3/8 Clincher Wire Black/Tan

- Makes the perfect economical trekking tire - The Excel has a reflective stripe on the sidewall, keeping you visible at night for city riding - If getting a reliable, high-performance trekking tire at an economical price is what you're after, the Overdrive Excel is the tire for you.

Schwalbe's Silento rolls quietly along pavement, and has just the grip for light off-road excursions. Schwalbe's KevlarGuard puncture protection helps prevent flats, too.

- Gravel-racing specific tire, derived from our experience in the biggest competitions around the world and feedback from Pro athletes. - Tread design inspired by the Scorpion XC RC. - Key features: Higher average speed on straight and fast lines, improved lateral grip when off-road cornering.

Retro RIDE – ride retro! The name is iconic. The large volume tyre has proven itself for use on cruisers and city bikes. It offers great comfort and stands for design and lifestyle. The tyre has the profile of the legendary Conti KKS 10 and is available in modern colours. A must-have for style experts.

The Ride Tour is at home on any surface: a real all-rounder Continuous center tread provides good rolling characteristics and ample traction when cornering. Reliable puncture protection thanks to Extra Puncture Belt Durable casing and long-lasting tread impress on all rides.

Fast, safe and comfortable — guaranteed! The Contact is the jack-of-all-trades among city and trekking tires. Its tread design is based upon the principles of bionics. A uniform center tread/belt assembly ensures a smooth and speedy ride on the road. Flexible shoulder lugs and fine sipes guarantee grip in curves and on loose surfaces. The overall tire construction rounds off the overall high quality. The ultra fine carcass fabric reduces the rolling resistance while providing a noticeably more comfortable ride. Reflective sidewall for extra visibility. Reflective Sidewall: REFLEX is 3M reflective is commonly known to be one of the most highly reflective material options. A thin, silver light-reflecting strip on both sidewalls that adds visibility and safety to Continental's city / commuter / urban tires.

For finding your way off-road. For more comfort. For the adventure. Be it the long tour or the shortcut on your way home, the Terra gravel series by Continental gets you there over rough and smooth. Choose another road, choose Terra. - A user-optimized tubeless system is specifically designed for road cycling demands. Easy to install and reliable in use. - ProTection technology gives our tires the perfect mix of fast rolling, grip, and puncture protection. Four plies under the tread and three in the sidewalls result in greater resilience and less vulnerability to damage. - A specifically developed tubeless bead seals through its unique shape and provides a stable fit on the rim.

An energetic cosmopolitan! Tires are a safety-relevant component of each bicycle. High speeds and the additional weight from the battery and drive of an e-bike of up to 50km/h make a special e-bike tire necessary. A high-quality additional rubber 3/180 TPI reinforced carcass forms the solid frame of the E.CONTACT. The SafetyPLUS Breaker puncture protection specially developed for the high demands on e-bikes, protects the tire reliably against punctures and cuts. The profile of the tire is just as at home on asphalt as on gravel and forest trails – a good all-around tire.

- Premium mobility for design enthusiasts. - Urban profile packed with the latest technology. - The perfect symbiosis between light-rolling and puncture protection reflected in this specialized tire designed for the City Jungle. - Faster? Not a problem with approval for E-Bikes up to 50km/h! PureGrip Compound Based on activated silica compounds, this technology was originally intended as a performance level compound, but after intensive development at our Korbach Research and Development Department Facility, an advanced new compound with outstanding grip and cross-country properties was developed. This new rubber mix, given the self-explanatory name "PureGrip", is ranked just behind our BlackChili Compound and is being used in our performance products both in the road and mountain bike sectors. While providing great grip, it is also long-lasting and highly durable—both characteristics of Continental tires, which are exclusively manufactured in the factory in Hefei (Asia). SafetyPro The new SafetyPro Breaker designed from nylon textile. Cross-woven textile fiber netting that is simultaneously robust and flexible. Maximum puncture protection with minimal added weight. The risk of punctures resulting from glass or sharp stones is substantially reduced. E50—Suitable for E-Bikes For our E-Bike tires, we relied on over 100 years of experience with moped and motorcycle tires. All of our city/trekking tires are rated to a standard speed of at least 25 km/h. Those tires marked e50 are also certified for S-Pedelecs. With their high-quality structure, puncture protection is high and the rolling resistance is low, offering protection from premature wear brought about by the additional driving force.

For your way off-road. For more comfort. For the adventure. Be it the long tour, or the shortcut on your way home. The new gravel Terra series by Continental gets you there. Made to get you over rough and smooth.

Many of the fastest riders in the world place their trust in these handmade German tubulars. The Competition is a world-class tire proven everywhere from the cobbles of Paris-Roubaix to your local crit series. The 180-thread-per-inch, 3-ply casing offers a velvety-smooth ride and the Vectran sub-tread provides exceptional puncture protection, reduced rolling resistance and a great road feel.

Traffic signal sprinter! The SportContact turns any bike into a racer. The 26 version helps the bike messenger meet those deadlines while the 700C tire gets the fitness biker into a speed frenzy. All this added speed for your bike with zero detriment to puncture protection and reliability! Reflective Sidewall: REFLEX is 3M reflective is commonly known to be one of the most highly reflective material options. A thin, silver light-reflecting strip on both sidewalls that adds visibility and safety to Continental's city / commuter / urban tires.

From Rural to Urban The energy-saving SUV allrounder that gets you to both Rural and Urban. The partner for your commute, running errands and the weekend tour. PureGrip Compound Based on activated silica compounds, this technology was originally intended as a performance-level compound, but after intensive development at our Korbach Research and Development Department Facility, an advanced new compound with outstanding grip and cross-country properties was developed. This new rubber mix, given the self-explanatory name "PureGrip", is ranked just behind our BlackChili Compound and is being used in our performance products both in the road and mountain bike sectors. While providing great grip, it is also long lasting and highly durable—both characteristics of Continental tires, which are exclusively manufactured in the factory in Hefei (Asia). Shieldwall system The ShieldWall system combines the optimum combination of high puncture protection and the low rolling resistance with low weight. This is made possible by an additional, all-round puncture protection layer, which consists of a finely woven cross fabric. This gives the tire a high resistance to punctures and damage. Despite its additional ply, the tire has a very good damping property and a high degree of flexibility to adapt perfectly to the ground. The revolutionary tubeless ready bead allows easy and uncomplicated mounting of the tire. For best results in sealing and in use, we recommend the use of the new Continental RevoSealant sealant. Tubeless Ready Developed especially for the mountain bike sector, this additional puncture-protection layer which completely encircles both tire beads makes our carcasses robust and impervious against damage and penetration from foreign objects. For maximum effect we combine ProTection with BlackChili Compound. The result: versatile, low weight and an attractive design. In addition, tires made using this technology can also be used as Tubeless Ready. Suitable for E-Bikes For our E-Bike tire we fall back on over 100 years' experience with moped and motorcycle tires. All of our city/trekking tires are rated to a standard speed of at least 25 km/h. Those tires marked e50 are also certified for S-Pedelecs. With their high-quality structure, puncture protection is high and the rolling resistance is low, offering protection from premature wear brought about by the additional driving force.

The Double Fighter with a fresh new design and in a multitude of sizes. With a robust rubber sidewall, it fears neither the city nor the countryside. It rolls along the asphalt effortlessly and in silence. Its shoulder lugs allow it to stay on the right track, whether on park paths or gravel roads. Ideal for making knobbly off-road tyres into a swift city racer.

The ideal choice for fixed gears, single speeds, and urban bikes, the Grand Prix Urban combines a modern profile design with the latest technology. It offers a race-tuned construction while simultaneously damping for comfort—the perfect mix for the urban ride. With Continental's unique and legendary BlackChili tread compound, produced only in Germany, they have revolutionized the sport of cycling. This compound answers the eternal question of the best balance of grip and rolling resistance for cycling. Regular test wins confirm the measurable and noticeable advantages for cyclists, established in the lab and on the road. The latest polymers, as well as specially developed carbon black particles and filler materials, guarantee ultimate performance. This tire also offers superior puncture resistance with PolyX Breaker technology, using an extremely resistant polyester fiber in a tightly woven crosswise pattern. The result is a very high fabric density, which makes the Breaker more resistant to foreign objects and especially resistant to punctures, while not affecting rolling resistance.

The Grand Sport Race encourages peak performance. The perfect blend of high puncture protection, comfort and smooth running makes it the ideal tyre for competitions and tours. Other plus points are maximum cornering grip and durability. The all-rounder is ready for every challenge even the biggest ones.

- Fast-rolling tread - Wire-bead

- Smooth tread offers minimal resistance - File tread on shoulders ensures cornering confidence

The Black Wall in K34 Tread is a great tire for any road bike. As avid everyday riders, Kenda knows what goes into a great commuter tire. Fast rolling, long life, and superb puncture protection are just a few of the reasons people prefer Kenda. Whether you're riding to the store or out for a weekend, Kenda will help you get safely where you're going. - K34 tread pattern - Made from quality Kenda rubber - ETRTO: 32-630 - Wire Bead

- Smooth-rolling tread pattern for street use - Deep grooves help sipe water away in wet weather

- Compound: ZSG AGILE COMPOUND - Breaker: TOUGH & FLEX SUPER BELT - Casing: Advanced Extra Alpha Cord

With its aggressive tread and versatile high-performance GravelKing casing, riders will experience great handling characteristics through a wide range of tire pressure and excellent traction on wet or dry gravel or dirt.

A do-anything combination of low rolling resistance, Hard-Case tread and sidewall protection, and a grippy, all-weather compound with siped tread for enthusiasts who want one tire for year-round riding. - Excels on the road in a variety of conditions - Hard-Case triple flat protection protects against punctures

- The next generation of tubeless tires. A truly thrilling ride. It's fast. It's reliable. It's light. - The patented MicroSkin construction makes this all possible. The rolling resistance is minimal! - All around cut resistance and puncture protection are extraordinary. - This is the absolute top model from Schwalbe! - The Schwalbe One Pro can also be used with a normal tube, but its true strengths are experienced only in tubeless form.

Schwalbe's Marathon Mondial is the ultimate touring tire ready to travel the world if you want. Handling is great thanks to their TravelStar rubber compound, and their Double Defense technology keeps it relatively light and high-performance while maintaining excellent puncture protection. Whether you're setting out on a cross-country bike tour, cruising on a tandem, or just want peace of mind during your daily commute, the Marathon Mondial is in it for the long haul.

Pasela is Panaracer's standard all around touring or urban commuting tire. Its comprehensive size range ensures that you can find a Pasela for most any usage. Ride it and trust it. - Steel (Wire) bead

The All Terrain is always up for adventure. From long-distance touring to light-duty offroading, this tire offers impeccable handling that won't let you down. Usage: Trekking / Comfort Conditions: Dry to Damp / Pavement to Hardpack Compound: DNS Casing: Durable Bead: Wire 26" Comp - Tube Type: 635g 32c Comp - Tube Type: 455g 37c Comp - Tube Type: 540g

FAAAASSSTT! The Nano 40c is built for speed, and let’s just politely say it delivers. A 40mm, rounded profile and an elevated centerline provide enough volume for lower tire pressures and a smoother ride while still reducing drag and rolling resistance. This makes for an all out gravel destroyer that can still appease those clamoring for a truly big cyclocross tire. Winner? We think so. So does everybody else. Don't believe us? Just ask. Everybody's irrefutable favorite, 'nough said. Usage: Gravel / Cyclocross Conditions: Dry to Damp / Hardpack to Sand - TCS Light/Fast Rolling: 530g, Dual DNA compound - Race Tube-Type: 470g, DNA compound - Comp Tube-Type: 550g, DNA compound