Make sure you are using the Swiss Army Helix formula and you can make your radius whatever you want it to be. To avoid pumps, remember the angle you came out as from the previous element has to be the same angle you begin with to avoid a pump.
I am slowly becoming the only serious designer here that isn't using Elementary... of course, I am using good old fashioned math so it's the same idea.
If you don't want a turn that pumps, and you use more than one element, keep the radius the same and make sure the end of the first element has no lead out, and the start of the second element has no lead in.
If you want my advice (not sure if you are asking but here it is anyway) -- I would design three or four coasters on your own and not post them. This is what I did when I first started using Elementary, and actually that idea came from Tyler. Just design for you man -- then once you start to really perfect things, then post a ride and see how it fairs. Posting the first ride you create with Tools is probably not going to get you instant rewards.