If they are the Spectrums, one may have a cracked gear. Search these messages for shay cracked gear and read on.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
I have two identical Shays. One runs nice & quiet, the other has what sounds like a gear noise. The sound changes as the speed changes. Can I use a drop of LaBelle oil on the Rods? I run HO.