Sometimes I try to make several shots with the Ninja Rope and they just don't fire.

Are there certain conditions that must be fulfilled? e.g. moving at a certain speed or firing at a certain angle?

No special conditions needed to rope.

So is it a glitch?
It's very noticeable in rope races.

When you swing off and make even the slightest contact with the geometry, it won't let you swing again.

Oh, I see. Thanks.

I've had this issue a couple times, it seems to occur when I'm moving at a high velocity IE. I've got the rope really long, start from up high and let go just pas the bottom point to essentially slingshot me far across the board. It could be a distance thing too, I know for certain I haven't come in any contact with the board while doing this. Just seems if I travel a distance at high speed without immediately reroping after letting go, I can't fire again.

You get one flip before you're boned. The roping is a bit of a failure.