Four years after its original Grail rim ‘brought tubeless technology to road, gravel and cyclocross bikes’, Stan’s NoTubes has introduced the new Grail CB7 and MK3 rims and wheelsets. The wheelset specialist notes that ‘today’s more versatile drop bar bikes demand a new kind of tubeless rim, one that’s as capable of crushing 200 miles of gravel as it is scaling above category climbs.’
Optimized for tubeless tyres and designed for disc brake-only use, the new Grail CB7 and MK3 rims and wheelsets ‘combine the best characteristics of classic ultralight road wheels with new levels of reliability, control and comfort’.
Grail CB7 and MK3 rims and wheelsets will be available from dealers, distributors and directly from notubes.com this month. Their release follows the more economical Grail S1 wheelsets that were launched in 2017.
The Grail CB7 rim is designed for 25-40mm tyres and a maximum pressure of 85 psi/5.9 bar (with 25mm tyre). Developed specifically for tubeless tyres and disc brakes, the Grail CB7 uses Stan’s patented low-profile rim shape, ‘putting material only where it’s needed’. At only 300g, each Grail CB7 carbon rim is claimed to be 30g lighter than even the lightest competing carbon gravel rims and over 100g lighter than many carbon road and gravel rims.
Stan’s add that rotational weight is the most important and noticeable area of weight savings on a bike, and the Grail CB7 wheelset ‘translates weight savings into outstanding acceleration and a serious advantage on climbs.’
The Grail CB7’s 21.6mm internal rim width creates a more stable base and optimizes tyre shape for improved cornering stability and handling. The shape of the Grail CB7 keeps larger tyres from folding over on the rim, even under the lower pressures and hard cornering of cyclocross and gravel races. The Grail CB7’s patented rim shape also helps to prevent tyre pinch flats and ‘makes tubeless setup faster, easier and more reliable’.
Incorporating Stan’s radial impact absorbing carbon technology (RiACT), the Grail CB7’s low-profile shape and proprietary carbon layup work together to help absorb road vibrations and distribute impact. Pioneered by Stan’s, based on a study of tubeless tires, the radial compliance of the Grail CB7 rim also helps eliminate pinch flats. The RiACT rim shape and layup process allow the Grail CB7 to soak up vibrations, ‘letting you ride faster with less effort and making this the most comfortable rim available for both road and gravel’.
The new Grail CB7 wheelset has already claimed a major podium with Geoff Kabush’s third place finish this weekend at the 2018 Dirty Kanza, a self-supported, non-stop, 200-mile-long endurance race on the gravel and dirt roads of the Flint Hills region in east-central Kansas.
The Grail MK3 is designed for 25-40mm tyres and a max pressure of 110 psi/7.6 bar (with 25mm tyre). Based on the original Grail rim shape, the new MK3 rim features lighter and stronger 6069 aluminium construction and weighs 440g. Lighter than the original Grail, the new Grail MK3 is also stronger, laterally stiffer and more resistant to dents, ‘making it ideal for longer rides both on and off the pavement’.
Slightly narrower than the carbon CB7 model, the Grail MK3’s versatile 20.3mm internal rim width and reinforced, low-profile sidewalls are built to handle the higher pressures of tubeless road tyres, low-pressure tubeless converted tyres and conventional tyres with tubes. Like all Stan’s tubeless rims, the shape offers a more secure connection and airtight seal when used with tubeless tires. Stan’s adds that its patented tubeless technology can ‘seal most punctures while you ride, for unmatched durability and peace of mind on every ride.’
Complete Grail CB7 wheelset options include a 1,277g Pro model featuring Stan’s precision CNC-machined Neo Ultimate Speedsync hubs with hardened steel ratchet and rapid five-degree engagement, Sapim Laser spokes and Sapim Secure Lock alloy nipples. The 1,360g Grail CB7 Team wheelset includes Neo Durasync hubs with 10-degree engagement, Sapim Force spokes and Sapim Secure Lock alloy nipples.
The Grail MK3 will be offered in a single wheelset weighing 1,675g and featuring Neo Durasync hubs, Sapim Laser spokes and Sapim Secure Lock alloy nipples.
Grail CB7 and MK3 wheelsets will be available with custom decal color options and multiple build configurations as a part of Stan’s Custom Wheel Builder at notubes.com/custom-wheelset.
Grail CB7 rims are automatically covered under Stan’s two-year carbon warranty program. Owners who register their wheelsets get five years of warranty coverage. All registered carbon rims and wheelsets are also covered by Stan’s lifetime crash replacement.
Grail MK3 rims come with a two-year warranty and one year of no-fault crash replacement.
Grail CB7 – Pro & Team
Uses: Gravel, Cyclocross, Road
Internal Rim Width: 21.6 mm
External Rim Width: 26.4 mm
Rim Depth: 19.3 mm
Optimal Tyre Sizes: 28-40 mm
Hubs: Stan’s Neo Ultimate with Speedsync 24-hole Front, 28-hole Rear (Pro); Stan’s Neo with Durasync 24-hole Front, 28-hole Rear (Team)
Spokes: Sapim Laser Black 1.8/1.5/1.8mm (Pro); Sapim Force Black 2.0/1.7/1.8mm (Team); Nipples: Sapim Secure Lock Alloy Black
Wheel Weight: 1,277 g (Pro); 1,360 g (Team)
Rim Weight: 300 g
Max Tyre Pressure: 85 psi (25mm), 70 psi (32mm), 55 psi (40mm)
Max Rider Weight: 86 kg or 190 lb (Pro); 104 kg or 230 lb (Team)
MSRP: Pro Wheelset – US$1,635; Team Wheelset – US$1,399; Rim – US$600
Uses: Gravel, Cyclocross, Road
Internal Rim Width: 20.3 mm
External Rim Width: 24.0 mm
Rim Depth: 24.5 mm
Optimal Tyre Sizes: 28-40 mm
Hubs: Stan’s Neo with Durasync 28-hole Front, 28-hole Rear
Spokes: Sapim Force Black 2.0/1.7/1.8mm
Nipples: Sapim Secure Lock Alloy Black
Wheel Weight: 1,675 g
Rim Weight: 440 g
Max Tyre Pressure: 110 psi (25 mm), 70 psi (32 mm), 55 psi (40 mm)
Max Rider Weight: 104 kg or 230 lb
MSRP: Wheelset – US$699, Rim – US$105
Stan’s NoTubes, founded and owned by Stan and Cindy Koziatek, forged a path for making mountain bikes tyres tubeless. Stan Koziatek devised the original NoTubes sealing system in 2001, the same system that today has become a preferred tubeless conversion system around the world. Stan’s NoTubes currently designs, produces and sells innovative mountain bike, road and cyclocross wheels, rims and hubs as well as a range of products for tubeless conversion.