I found that by trying the long shank coupler on the rear I was able to get around 18" curves without "throwing" the following car off the track. If your track is fairly level, the "long center shank" will work fine. If you have a lot of dips and rises, you may find that the "long over shank" will work better, as the Forney is a real stiff locomotive. I used the Bachmann E-Z Mate Mark 2-the one with the metal spring. You may also help the situation if you attach a long shank coupler to the car you wish to have directly behind the locomotive. I found that having one of the passenger cars first in line made life real easy. Best of luck to you. John Tumolo Britcarfan@aol.com