If the player talks to the Bike Shop owner in Cerulean City while pressing B through the dialogue, it will temporarily enable "instant text", a condition in which the frame delay between printing each character is 0.
This trick generated debate by Pokémon speedrunners as to whether it would be considered a glitch, for the sake of setting down rules for Red's Any% glitchless category. The glitch was allowed in the category at one point, for the same reasons as the Marowak ghost skip but was later prohibited from it. "Instant text" runs need to take into account various possible routines that may be called throughout the remainder of the game that would set the text speed back to what it was previously, significantly changing the route, which was one of the reasons cited by opponents to its allowance in Any% glitchless.
The instant text will persist until: The player opens the start menu. The player heals their Pokémon at a Pokémon Center. The player loads a Yes/No box. The player speaks with the Bike Shop owner again.
CauseWhen the player activates the two message boxes with the price of the Bicycle (Bicycle ₽1000000) and the text "It's a cool BIKE! Do you want it?", the game sets bit 6 of memory address D730 in order to instantly display the text. Due to an oversight, bit 6 remains set when exiting the menu with B.
A more detailed description of this glitch and other events that enable instant text (but are unaffected by the glitch) by Decon082 may be found here.