Folding the antenna is going to hurt the matching of that antenna.
Its still going to work, just not as good, and a bunch of signal will be reflected back into your RFM, meaning it will have to output greater power to get the same signal strength across the same distance.
Makes sense?
Making your helical antenna on-the-fly without any considerations is probably not a good approach. Size, diameter, gauge, length, all matter.
I hope that makes sense.