Curious as to how many of you with older E-tracs notice that after time, the upper shaft clamp assembly doesn't hold the lower shaft tightly in place any more? Mine are not allowing the lower shaft to 'slip' , but the lower stem can shift the angle of the coil on occasion, when I'd rather it stay straight and tight. Does anyone know if these can be repaired or tweaked in some way to apply more pressure to the lower shaft? i ordered two new upper shafts to have on hand, but would rather repair what I have, if possible... Knipper