Board Thread:Theories and Speculation/@comment-34277398-20180522015234/@comment-734582-20180523185712

BlazeRelease wrote: Like take a look. Naruto summons Gamabunta, after he gets powered up by Kurama's crazily powerful chakra. Before that, Naruto already had crazily large chakra reserves, more than even jonins. Yet, he couldn't properly summon an average size toad. His first try was a tadpole I believe. Actually, Naruto didn't have massive reserves. According to Kakashi, about 2-4 times as much as him. It's kurama that gave him the massive amounts of chakra.

BlazeRelease wrote: if it was just reserves, then Hashi should have been able to easily do the same feat Hashirama cannot force a Biju into a summoning contract. He can subdue them, but not control them. He also never actually summoned Kurama, which is why he wasn't know for it.