BodyAngularVelocity randomly stops working sometimes?

so i have this simple script

	script.Parent.Parent.Parent.Parent.PropellerCenter.SpinSpeed.AngularVelocity =*5,0,0)

which basically each time a value changes sets a body angular velocity to its value multiplied by 5 (in the x axis). the problem is, it sometimes just randomly stops(i mean the part stops rotating). i have tried creating a while wait(0.5) loop but that didnt help either. is there anything i could do to fix it or is it just a roblox issue which i cant fix