Seven Cycles - XX Grade
What is XX?
The XX grade is the highest grade in pursuit of "perfection" for every part of the frame.
Seven Cycles starts by identifying all the latent elements that can be improved from each part of the frame, ignoring the cost. I put it in one package.
The bicycle industry has used "lightness" as a marketing strategy for decades, but frames have continued to gain weight year after year. The evolution of components such as disc brakes, thru axles, tapered column forks, wide tires, etc., has increased the weight of the bike due to the required specifications.
With the XX grade bikes, we've reimagined every inch of the frame and shaved off the flab hidden in the list of things the industry has "improved" over the last decade. Based on the appropriate know-how and design unique to Seven's thousands of manufacturing achievements, all of the new build techniques that have passed the endurance test will be applied to the XX bike.
The advantage the XX bikes get is that they can be built to frames that are 113g to 311g lighter than the SL grade without sacrificing performance or durability. Seven considered how to realize this ultimate custom frame by weighing each part in grams. Grams, not ounces.
Here are eight designs that make it happen.
1. Asymmetric Fastback Dropouts
The non-drive side uses standard flat-mount dropouts, but the drive side is paired with asymmetrically designed thru-axle dropouts for a weight savings of around 60 grams .
The anti-drive side dropout has a pedestal for the brake caliper, so it should be about 10cm long from the center of the axle to the edge of the brake rotor. This is a very long dropout and is much heavier compared to tubes of the same length. On the drive side, the dropouts need only be four centimeters from the axle. This asymmetrically designed dropout is not only lighter, but also stiffer. (Seven dropouts are among the stiffest in the industry)
2. Asymmetric Chain Stay
The asymmetric chainstay saves about 6 grams of weight while increasing drivetrain stiffness.
Dropouts originally require independent left and right chainstays, so by appropriately designing clearances for parts such as chainrings, tires, and cranks on both the drive and non-drive sides, we were able to raise that performance to the limit. I can. The benefit of this asymmetrical design is that the weight savings of a few grams is a bonus, resulting in a significant increase in stiffness.
3. Modified BB Shells
Approximately 14 g of weight is reduced by further cutting the BB shell. This has no ill effect on the frame.
At SEVEN, the BB shell is machined and threaded after welding. The result is a truly warp-free platform, but the CNC machining process is more advanced than usual to shave off excess mass without sacrificing durability or stiffness.
4.Modified Breather Hole
All the tubing that makes up the frame has a hole called a breather hole for passing the inert gas necessary for welding. This hole is expanded to the maximum without compromising durability and rigidity, achieving a weight reduction of about 12 g . It's a place that can't be seen from the outside, but I don't cut corners.
5.XX Tube Butting
Butting the tube saves 30-45g of weight .
Seven has introduced a new butting system, which has made it possible to make it even lighter by an average of 40 g than the proprietary butting process that has been refined repeatedly.
By arranging the selection of tubes that make up the frame and their profiles (diameter, wall thickness, etc.), we achieve a weight reduction of 30 to 60 g .
The X-Series upgrade takes a unique approach to unleashing the true power of American-made titanium tubing.
7.Flat Mount Brake Adapter
The seven original flat mount brake adapter has been further refined to reduce weight by approximately 13 g without sacrificing braking power or response.
8.Compact frame design
A slightly more compact frame design saves about 18 g of weight .
Increases top tube sloping by about 2 degrees over Seven's standard design. As a result, rigidity is increased, and excess parts can be scraped away.
Thinking More Deeply About Weight
A lighter frame (or component) has three effects on a bike.
1. Better performance.
2. Lighter weight can increase suppleness.
3. Generally speaking, weight reduction is an act that shortens the life of a product.
In pursuit of lightness, the bike has the above three influences.
In creating the XX grade, SEVEN carefully avoided the challenges of durability and product life while incorporating the advantages of 1 and 2 above. The goal at the heart of its design is to achieve weight reduction without sacrificing frame rigidity or performance. It is something that responds at a higher level.
(Note: XX bikes are not carrier/rack mountable and are not recommended for riders who require an ultra-stiff drivetrain (9 or 10 on the stiffness rating scale).)