Train system not moving

Help and Feedback Scripting Support
#1

I want to make a train movement system.
Inside my Drive seat (inside the first carriage named appropriately, and welded per carriage), I have the following script:

local Velocity = 0

script.Parent.Changed:Connect(function(typEe)
	if typEe == "Throttle" then
		local Input = script.Parent.Throttle
		repeat
			Velocity = (Velocity + Input)
			if Input * Velocity / math.abs(Velocity) == -1 then
				wait(script.Parent.Parent.Parent.Data.Acceleration.Value)
			else
				wait(script.Parent.Parent.Parent.Data.Acceleration.Value)
			end
			if Velocity > script.Parent.Parent.Parent.Data.MaxSpeed.Value then
				Velocity = script.Parent.Parent.Parent.Data.MaxSpeed.Value
			elseif Velocity < 0 then
				Velocity = 0
			end
		until script.Parent.Throttle ~= Input
	end
end)

while true do
	wait()
	vectorpower = script.Parent.Parent.Parent.Data.MaxSpeed.Value * script.Parent.CFrame.LookVector
	for i=1, script.Parent.Parent.Parent.Data.Carriages.Value do
		local vel = script.Parent.Parent.Parent[i]["Move" .. i].BodyVelocity
		vel.MaxForce = Vector3.new(
			(vectorpower.X > 0 and vectorpower.X or -vectorpower.X),
			(vectorpower.Y > 0 and vectorpower.Y or -vectorpower.Y),
			(vectorpower.Z > 0 and vectorpower.Z or -vectorpower.Z)
		)
		vel.Velocity = Velocity * script.Parent.CFrame.LookVector
	end
end

(typEe is spelt that delibarately as type is global variable)

Any idea?