Okay, since my last post on July 12th, I have converted to the EZ- nickel silver track. My layout is on two 4 x 6 foot sections joined together to make a 6 x 8 layout. I have 22 degree curves on the main line, and 18 degree curves on the two bypass lines. The engine is jumping the track, with the front wheels usually coming off first. I have checked the track joints carefully, and they are smooth. I suspect I need to send the engine back to Bachman for repairs. I picked up an older Bachman diesel engine off ebay and it never derails.