Custom Speed

LocalScript

local frame = script.Parent
local add = frame.add
local sub = frame.sub
local speed = frame.speed
local Player = game:GetService('Players')
local currentSpeed = 16
local maxSpeed = 50
local minSpeed = 0

local function addSpeed()
    local player = Player.LocalPlayer
    if currentSpeed < maxSpeed then
        currentSpeed = currentSpeed + 1
        speed.Text = 'Speed: '..currentSpeed
        player.Character.Humanoid.WalkSpeed = currentSpeed
    end
end

local function subSpeed()
    local player = Player.LocalPlayer
    if currentSpeed > minSpeed then
        currentSpeed = currentSpeed - 1
        speed.Text = 'Speed: '..currentSpeed
        player.Character.Humanoid.WalkSpeed = currentSpeed
    end
end

add.MouseButton1Click:Connect(addSpeed)
sub.MouseButton1Click:Connect(subSpeed)