Dashing script doesn't change the player's velocity at all, but it doesn't show any errors?

So, this script isn't finished yet, but I'm trying to make a dash script so that whenever you double-click w, a, s, or d, it does a dash animation, and launches you in a direction based on which key you pressed. It makes the character jump, but the only thing launching it forward, is me pressing w when I'm double clicking.

Server:

local repStorage = game.ReplicatedStorage
local dashingEvent = repStorage:WaitForChild("Dashing")

dashingEvent.OnServerEvent:Connect(function(player,key)
    local char = game.Workspace[player.Name]
    local humanoid = char.Humanoid
    local rootPart = char:WaitForChild("HumanoidRootPart")

    if key == "w" then
        humanoid.Jump = true -- It does this, so I know that this if event isn't just ignored.
        rootPart.Velocity = rootPart.CFrame.lookVector * 100 -- This should push the player's character forward, right?
    elseif key == "a" then
        -- There's nothing here because, once again, it's not finished yet.
    elseif key == "s" then

    elseif key == "d" then

    end
end)

Client:

-- This script seems to work just fine, but I decided to post it just in case the problem lies in how I fired the server or something weird like that.
local player = game.Players.LocalPlayer
local char = player.Character
local mouse = player:GetMouse()

local clickCount1 = 0
local clickCount2 = 0
local clickCount3 = 0
local clickCount4 = 0
local doubleClickCooldown = 0.2

local db = false
local dashCooldown = 1

local repStorage = game.ReplicatedStorage
local dashingEvent = repStorage:WaitForChild("Dashing")

mouse.KeyDown:Connect(function(key)
    if key == "w" and db == false then
        clickCount1 = clickCount1 + 1

        if clickCount1 >= 2 then
            dashingEvent:FireServer(key)
            db = true
            wait(dashCooldown)
            db = false
        end

        wait(doubleClickCooldown)
        clickCount1 = 0

    elseif key == "a"and db == false then
        clickCount2 = clickCount2 + 1

        if clickCount2 >= 2 then
            dashingEvent:FireServer(key)
            db = true
            wait(dashCooldown)
            db = false
        end

        wait(doubleClickCooldown)
        clickCount2 = 0

    elseif key == "d" and db == false then
        clickCount3 = clickCount3 + 1

        if clickCount3 >= 2 then
            dashingEvent:FireServer(key)
            db = true
            wait(dashCooldown)
            db = false
        end

        wait(doubleClickCooldown)
        clickCount3 = 0

    elseif key == "s" and db == false then
        clickCount4 = clickCount4 + 1

        if clickCount4 >= 2 then
            dashingEvent:FireServer(key)
            db = true
            wait(dashCooldown)
            db = false
        end

        wait(doubleClickCooldown)
        clickCount4 = 0

    end
end)

Any help is appreciated!