Sasuke will never catch up to Naruto...

1. Right now Sasuke slightly better than SM Naruto. WAIT!!! Before you attempt to flame me, I hope you realize that the only difference between sasuke with MS and EMS is that he doesn't go blind. There are no other powerups, no extra techniques, no increase in chakra. His chakra got more evil but who cares. The fact is.... Itachi did more with MS than sasuke ever could with his EMS. So i repeat- Right now Sasuke is slightly better than SM Naruto.

2. Even before becoming friends with the kyubi, Naruto had full control of the kyubi's chakra. He learned new techniques and increased his chakra control. And let's not forget he that Naruto became the fastest character in the manga. At this point, Naruto passed sasuke.

3. Now Naruto and the kyubi are friends. Naruto has gained unlimited chakra, immunity to genjutsu, and the kyubi's experience. Sasuke has shown no growth since the Danzo fight.

I think with the help of Orochimaru, that sasuke will get the Rinnegan but I still don't think it'll be enough. While Naruto is gaining fighting experience and becoming better at fighting with his new powers, Sasuke hasn't shown any growth. If Sasuke gets the Rinnegan, he could potentially become as powerful as Naruto but not without lots of training. How long did it take Nagato to become good with the Rinnegan? How long did it take Sasuke to get good with the Sharingan? And like I said earlier, Itachi with MS is better than Sasuke with EMS- no debate.

At this point, base Naruto and base Sasuke are equal.

Sasuke couldn't use MS and Naruto wasn't using SM, but MS>SM. Naruto admits he couldn't beat sasuke yet.

Naruto held his own against Obito with Rinnegan, Sharingan, and the past jinchuriki as his paths.
**Before becoming friends with the kyubi**OP

Naruto is holding his own (while protecting Kakashi, Bee, and Guy) against Edo Madara and Obito.

Sasuke will never catch up.