OK, in designing and building our rollercoaster, we've been using this "food grade" plastic tubing to do the vertical loops and whatnot, hanging/suspending the loops and track from posts on the side and a top rail system. We finished a bunch of loops, got the system to work just fine, then we run it about 30 times in order to otimize certain parts by moving (in amounts of a quarter inch) the track sections by pulling the wires up or down... the wire that suspends it... OK, so it works. We leave the coaster for 5 or 10 minutes, redrop, (not touching a thing) and the system fails... Not only that, but then it wants to slow down in spots where, previously, we had no question about it working because it showed an AWESOME amount of energy. It is extremely annoying but something needs to be done. Anyone here have any good ideas about how to improve the speed of the ball or anything else (we're using a 16mm diameter stainless steel ball bearing, and the plustic/rubber hosing, about 1" diameter... possibly a little more)? It's hard to suggest, based on the setup that we have that you guys AREN'T able to see, how we can change the track, but perhaps ways to increase the efficiency of the ball on each trial? Thanks in advance!