Sorry you're having trouble Andy. I wrote an article about similar experiences you can take a gander at in The Academy regarding clearance problems that might help. Without tearing out something to remedy this is going to be difficult, if not impossible. I'm having trouble visualizing the whole picture, but it sounds like you have the bridge too close to the curve. You should have enough straight track, preferably no less than one foot (30cm) before going into a bridge or tunnel. Try and straighten out the lead into the bridge. Something else that scares me is that you say you have a steep grade leading up to the bridge as well? If you level that out too fast, you're in for a whole other set of problems you don't need to deal with. Can you be more specific about distances, elevation measurements in standard or metric grade percentages, so we can help you better? George.