Lego HP help please!

Hey, i'm on سال 4 of Lego Harry Potter and its the first stage at the quidditch world cup where the death eaters attack... i can manage to complete the first part of the stage, rescuing the Weasley's but for some reason, i cannot go ahead with the سیکنڈ part that requires having to jump on the springboard over the three fires to get to Harry.

I've tried everything possible; using Hermione, Ron and Ginny, i keep dying... i tried timing the height of the character before jumping, still dying, i tried it at night and in the morning... i don't wanna be stuck on this stage forever!!!!