@Ted S posted:
@jini5 I had exactly the same experience with my first and only MTH A-B-A set. "Run smoothly at 2 scale mph" my butt!! (At the time, MTH tech support told me that performance was "within specs." They eventually changed their catalog copy to "runs smoothly 5 scale mph.") There really is no other solution. I still have my FT's, but after that I switched to Lionel with the back-drivable gears. In the early 2000s Lionel had its own struggles with the "Odyssey lurch." But they learned from the issue and engineered an effective solution instead of milking a cash cow.
I'm not a DCS expert and my DCS set is packed away right now. It's definitely possible to turn the cruise control off. Either browse the menu options on your remote, or check the manual. I'm sure it's mentioned in Barry Broskowitz's guide to DCS, if you have that.
By "turning around," what I meant was to put the loco with the tach reader motor end closest to the train. I guess if the tach reader is on the rear motor, you could try pulling the train with only that unit, just to see if it still bucks. I would like to know if the root cause is mechanical, or a timing "feedback loop" caused by the speed control.
Ted, thanks for more insight. Its funny you mention that Lionel has the back drivable gears. I had and sold a Visionline big boy that would not maintain cruise control going down a hill when it had no consist behind it. I sent that loco back to lionel because of the coal load depletion was not working. At the same time I mentioned to them that loco will not hold cruise control down my grade. As the loco started downhill, the weight of the loco was pushing it at a higher speed. When it got to the bottom, The cruise would reengage and it would run as expected. I made them a DVD of the downhill run. They sent it back to me stating that since their grade was not as steep as mine, they had no way to test/diagnose the problem. They even stated they watched my DVD but still had no solutions. I felt this was a big time cop out on their part. They could watch first hand what was going on. So..........in the end concerning the Lionel Vision line Big Boy, I am guessing since those gears are back drivable, thats probably why that loco could not maintain the cruise going down hill. Sounds simple to Me. But Lionel had no idea?
Anyway.......Back to MTH.....I am beginning to see there may not be any solution......Just the "nature of the beast".....Maybe removing traction tires might help as postd above, but again I feel like I shouldn't have to start modifying stuff. The flywheel with the Tach reader is located in each A unit at the rear truck. Therefore the trailing A would have the non tach motor in the front of the A which would be up against the consist. Following motor leads back to the control board shows that both front and rear motor are under the same connector.That would tell me that both motors are getting the same amount of voltage. Again, no binding when turning flywheel manually.
Do you think there might be a way to keep that truck on the rails by using a stronger spring or using spacers or.....................?????
Again, Nature of the beast here? Hope not
