How To Make Rapid Speed up Buttons
From Legacy Roblox Wiki
Introduction
WalkSpeed is what it sounds like, the speed at which your character walks. Go into solo mode in Roblox Studio and select yourself. If you look at your Humanoid, you will notice in the Properties panel a new value entitled "WalkSpeed" set to a default value of 16. The higher this value, the faster. Negative Values cause your controls to reverse.
Script
function onTouched(part) if part.Parent ~= nil then local h = part.Parent:findFirstChild("Humanoid") if h~=nil then h.WalkSpeed = 80 -- go five times faster than default speed. end end end script.Parent.Touched:connect(onTouched)