Madara already had a insane amount of chakra, but as the Ten-Tails Jinchuriki, his chakra levels are even more insane, as the Ten-Tails was stated to have immeasurable chakra.

1. Sasuke

2. Madara

3. Obito

4. Itachi

5. Shisui

6. Izuna

@Duncril01 The Juubi does have immeasurable chakra, which is why Jura is so strong, however Madara not being in full control of the Juubi means he doesn't have the full potential that he needs to beat Sasuke.

When was it stated that he had no control over the Juubi? It just makes no sense.

Hard one