Where did you put the suitcase weights? On the head that moves?
On the vertical front frame that carries the 3 point pins. One bracket on each side (note, I made mine from schedule 60 angle iron built in the shop to accept Kubota suitcase weights, one 100 pounder on each side), but I believe if you download the Erskine manual, it has their address and phone number and I would not be at all suprised if they would sell you their brackets that will require welding on (I welded mine on). His brackets accept John Deere Suitcase weights, I fabbed mine for Kubota weights, which are different than JD weights.
Adding 100 pound weights, one on each side, really improves the overall performance and pretty much eliminates the unit hopping around on a cut in dead hardwood stumps.
Im not sure what carbide cutter teeth the Bauma comes with but the reason I purchased my Chinese clone grinder was it mounts the industry standard Greenteeth and Green Manufactiring is local for me and I can buy them direct from them. 20 minute drive and no ship cost. Nice folks too and they offer a regrinding service for their teeth as well.
Really, the only difference between yours and mine is, the rear shield on mine is thick rubber whereas yours is metal.
The big detraction for people on here is the cost but I look at it this way, I own it, I can use it when it's convenient for me and they hold their value so I can resell it if and when that time comes.
I know the small Bauma grinders take only Bauma supplied carbide teeth whereas mine takes the Greenteeth and my teeth are indexable to 3 cutting positions as well. You will dull the teeth, that is a given.
You always need to run it at 540 rpm. The faster the wheel spins, the more efficient the machine is.
Mine requires 2 sets of remotes. One set for the swing and one set to raise and lower the cutting wheel and each set has it's own flow control valve so I can regulate the swing speed as well as the vertical up and down rate.
Finally, make sure to slip the slip clutch on the business end of the grinder. It's there to protect your tractor as well as the stump grinder gearbox.
Have no idea what you gave for it but I do know a new Erskine as well as the Landpride swing stump grinders are selling for around 5 grand presently. The Erskine as well as Landpride as well as my Chinese clone machine are basically all the same units. The Landpride as well as the Erskine and mine all have rubber pivoting back shields.
One thing I like about mine is it's ability to cut stumps to 10" below grade, so when I cut one, I just rake the chips back in the hole and call it good.
Have fun and be careful as they tend to throw wood chips out from under the shield anyway. My wife was watching me grind a stump the other day and got smacked in the forehead with a wood chip. Not an issue with me as I run it with a cab tractor. I have a really huge softwood stump I need to grind. It will require multiple passes as it's 5 foot across and grows to 7 foot at grade line. Old dead weeping willow. Glad it's gone, dirty tree. All got roasted in the burn pile last year. Looking at 3 maple stumps, 2 apple tree stumps and more to grind. All big ones too.