Stan's No Tubes have launched the new Grail rim to cater for the popularity of wider tyres, such as those that we're seeing on the latest endurance and gravel bikes. 

The Grail was actually developed when GT approached Stan's about a year ago when developing their new Grade road bike. GT wanted a wider disc-specific rim to cater for the wider tyres the bike can accommodate. The Grail was the result.

With a 21mm internal width and 24mm external width, it's the company's widest rim to date. Weight is a claimed 460g, Stan's telling us they built it to be durable for the sort of all-terrain riding the Grade, and bikes like it, are capable of, so weight wasn't the main focus, strength was.

The Grail is wider then than the company's Iron Cross cyclo-cross rim but about 75g heavier. However, where the Iron Cross has a maximum inflation limit of 45psi, the new Grail can take up to 125psi, making it more suitable for road and mixed terrain. 

The rim uses Stan's unique rim profile, which incorporates their Bead Socket Technology. This is essentially a sidewall that is 2-4mm lower than a regular rim, and which secures the tyre bead firmly into place. Once it's locked in there it's not budging, and in our experience makes running road tubeless a doddle.

Wide tyres are becoming much more commonplace in road cycling, even the pros are starting to ditch their 23mm tyres in favour of 25mm. And away from the racing world everyday riders with no interest in racing, but an interest in comfort, durability and exploring trails away from the road, are starting to embrace wider tyres. Wider tyres though need wider rims, and that's where the new Grail comes in.

The rim will be available in 24 to 32 spoke hole drillings, with GT using a 28-hole rim on their new Grade.  No word on pricing or availability yet. 

www.notubes.com