As a young boy in the eighties around 87 I remember my mum renting out a video. It was about a group of young people who for some reason came across something that turned them into these ninja's in black suits. Each one had a different coloured belt. And I think they could shot round in the same colour as they're belt. Anyway they won what ever battle they faced and at the end of the film gave up or lost there powers and they saw something and raised up there hands in this triangle shape and realising they had no powers did a runner. I know it sounds power rangers but it wasn't if anything the power rangers concept then stemmed from that. So does anyone have an idea or clue as to what this film was?

Ninja Kids (1986) (http://www.imdb.com/title/tt0199830/) ?