Hi, i have just bought a lovely Hornby RS508 Flying Scotsman Train Set. I don't know why Hornby decided to put first radius curves in as a big 4-6-2 does not suit first radius. Anyway when i tested it with the curves it hated them, (i did clean them). I have serviced the engine and cleaned the wheels, etc. I put the engine on some Hornby 3rd radius nickel silver curves and it only managed to pull 3 coaches at a slow speed. I don't know what to do so could anyone help? Thanks