My DRGW 455 K runs sweet and quiet but it has this little anoying quirk after a few loops around my indoor layout I will stop the loco and try to reverse it,some times it reverses some times not. When it does not reverse I noticed the 2nd axle lifts up and the siderod jambs. If I pull rod down loco runs ok.Siderod has a joint between 2nd and 3rd axle to allow the rod to flex as drivers negotiate rough track, however rr track is perfectly flat. This also will happen if loco is run a few laps in reverse then stopped and I try to run it forward . I'm starting to think that problem is related to prior post about loose counterweights. There is a lot of play in the siderod /counterweight part of the mechanism and I wonder if that is causing lock up problem as motor /gearbox runs smooth as glass. Anyone else having this problem???, Any help would be appreciated.