That's for road bikes. I don't know what the UCI says about mountain bikes, but since their introduction in the 80s, we've gone to clipless pedals, front and t

That's for road bikes. I don't know what the UCI says about mountain bikes, but since their introduction in the 80s, we've gone to clipless pedals, front and then rear suspension, 29" and 27.5" tires, disc brakes.