The Atlas Code 83 flex I've bought has had one sliding rail and one spot in the middle where there is a break in the ties on both rails (i.e 2 sections of ties). I've never seen one with 2 sliding rails.
Jim
I've never heard of or seen any Atlas track where both rails slid.
Send Atlas an E-mail and ask them. Do they both have brown ties and smaller spike heads??
The only differences listed on the Atlas web site are whether the track has wood or concrete crossties. Perhaps Atlas changed to a different manufacturer in China and you have track from two different suppliers.
http://www.atlasrr.com/Trackmisc/hocode83.htm
When I was putting down the track on my layout, I did find that I had one section of Atlas code 83 flextrack that had both rails that slid. I just used it on a straight section to avoid any issues with it, and I now can't even remember where it was that the track was put in with.
Kevin
http://chatanuga.org/WLMR.html
http://chatanuga.org/RailPage.html
Atlas claims that both rails are moveable.
Link:http://www.atlasrr.com/superflex.htm
Thats what I want.
Walt