My daughter brought home a friends Tesoro Sidewinder Micro Max and wants me to see if it operates correctly............ (never seen one) The owner has told her that chatters quite a bit. I first noticed that the bolt that attach's the coil to the shaft is metal (appears stock), is this normal for the Tesoro machines? I'm also not at all familiar with this "Retune" feature, what does this do and how doe it work. Any comments or help would be appreciated. The overall condition of the unit appears to be VERY GOOD. Thanks