I have recently purchased a brand new Bachmann Spectrum DCC Sound 2-10-2 DM&IR. After testing, I have found the following:
The locomotive jerks uncontrollably in forward and rearward operations and I can see the driver wheels binding to a stop each half-revolution. The 4th main driver wheel set "slaps" the sides of the rails with each revolution of its turn.
I believe this to be one of the reasons why this locomotive jerks when it is operating.
As this is a brand new, factory-sealed locomotive and I have found the exact same problem to exist with a brand new, factory-sealed 2-10-2 DCC Seaboard locomotive, this leads me to believe that these are not one-off issues but a systemic problem with this particular Bachmann engine.
I would like to find out if anyone else has encountered this problem.
LOYRR
That's pretty much how mine ran too, along with a 2-8-0 that died not 30 minutes later. Send it back. I'd say it's a dud. 100%
Do a search on the forum and you will find others have had the same problem.
I sent one back to Bachmann twice for the same rail slap and they replaced it with a heavy mountain on my request.
Recently i purchased a Chicago 2-10-2 and they must have solved the problem as it runs much better.
Smooth and no slap.
Bob
My 2-10-2 w/o sound runs fine, as does my heavy Mountain with sound. Guess I lucked out ...