Leap across the gap here and continue up the hill a short way, you will see a flaming tyre rolling down the hill towards you. Quickly make a 180 degree turn and jump back across the gap. After the tyre has safely deposited itself in the water, jump over again and continue up the hill, watching out for the occasional small flaming rock that will roll down.
If you are quick enough at jumping the gap and running to the right, you will not need to avoid a second tyre.
Enter the cave and climb the pair of ladders. At the top continue to the right.