After trying to find the cause of low amplitude on a 'well used' Waltham Riverside (on-going), I decided to clean a (much healthier looking) 16S Elgin Veritas 23J Grade 453 I recently bought. On stripping down, all looked pretty good apart from a broken 4th wheel jewel (replaced) and possibly the roller jewel ... I fitted a new mainspring and cleaned + oiled. The gear train seems good to me - the slightest turn of a winding stem sets it moving, as does an air blower on the escape wheel. Without the pallet fork in, the air blower sets the balance moving nicely, face up and down. So when I got it all together I was expecting the balance to spring in to life as soon as I started winding, and good amplitude. But .... amplitude ~ 160 deg. So I'm at the same stage as the Waltham - gear train and balance seem ok, but hardly any amplitude. After the Waltham it's a bit dis-heartening to be in the same position. Is there any other testing I could be doing on the gear train + balance to show that all is working correctly? The roller jewel has been replaced (I checked that it's not loose), BUT is not vertical. How critical is this ? It might be a clue that I'm getting weird readings on the timing machine - with the roller jewel lined up by eye, it's showing about 9 m/s beat error, Wouldn't that look way out ?