сначала погугли, потом жуйна мтбре тонна байков, есть много ревью.
Фишка темы-именно в доступности: купил колёса, вклячил в свой старый 26ер или циклкроссер и катай счастливый.
копи-паст с мтбр
жуй
Откроем в свое время, пока пресс-релизов подождём.
Мне понравилась эта статья: http://mountainbike.about.com/od/buy...50B_wheels.htm
и ответы: Question: What is a 650B Mountain Bike and Why Would I Want One?
Simply put, 650B is a wheel/tire size. In inches, as compared to the other two readily available mountain bike wheel sizes of 26" and 29", 650B wheels fit right in between at about 27.5".
Answer: Much like 29" mountain bikes, 650B bikes are are growing in popularity. It is hard to say if they will stick around or disappear in a few years, but they are an interesting option that for the time being, is becoming more and more available.
So why would you care about 650B mountain bikes? Well, there has been a lot of debate about wheel size in the mountain bike industry. The basic premise of the wheel size debate is that we came to our current standard of the 26" wheel somewhat arbitrarily. The standard of the 26" wheel size was established long before mountain bikes came around. So nobody can say that 26" wheels are and always will be the perfect size for mountain bikes.
If this all sounds familiar, it should. This is the same argument the 29" wheel crowd has been using for years.