Graduated Piers

[BobZ]

Just purchased a set of piers to be used with HO EZ-Track. Each pier was placed where 2 sections of track come together. Problem is  engines will not climb the 'ramp' with any rolling stock attached. Some wont climb at all. EZ-Track straights are 9" long. You wind up with a grade of a little over 5.5%. The rise is 3.5" and the run is 62.75. What would be the 'max' grade I should try for?
Thanks

[ACY]

You should have better results with a 2% grade, the most I would do is 3%
The steepest grade until recently on a mainline in real life was a four and a half percent grade on Norfolk Southern in North Carolina. The Pennsylvania Rail Road formerly had a five and a half percent grade in Madison Indiana. At present the steepest grade is on the Santa Fe with its 3% grade at Raton Pass New Mexico.
Being an engineer I have done some real life calculations to give you a rough idea:
For each 1% of ascending grade, there is an additional resistance of 20 pounds per ton of train compared to on level, straight track it is only about 5 pounds per ton of train. Therefore, a locomotive in real life, can haul only half as many cars up a quarter of a percent grade than it can on a level grade.
Additionally when it comes to curves, 1 or 2 degree curves are the most common on mainlines. Sharp curves also are limiting to the pulling ability of a locomotive.

[BobZ]

ACY, thanks for the info. I will keep the run to 10' min. That will give me grade of 2.9%. 15' run - 2.4% grade, 20' run - 1.5%.