Why does Naruto have so much chakra

Why can't Naruto switch to Bijuu mode like the other Jinchuuriki?

The answer is he can but chooses not to, instead he uses the six way sage mode which is the chakra fur and everything. In the movie Naruto the last, you can see that he summoned Kurama to fight and draw symbols on the moon. This shows that he can use Kurama whenever he is feeling.

the direct quote from naruto wikia

The Six Path Wise Mode (ik 仙人 モ ー ド, Rikudō Sennin Mōdo) is a form that strengthens the user's abilities to a far greater extent through the use of the Six Path Sage Chakra. It is a divine state that Hagoromo Ōtsutsuki gave to those who have an iron faith and have the courage never to give up. The only hallmarks of Six Paths Sage Mode are Naruto's eyes: his eyes are yellow, his pupils are a cross of vertical fox slits with horizontal toad slats, and there is no pigmentation around his eyes that would otherwise mean the standard sage mode . Naruto retains the ability to switch to Tailed Beast mode, which is comparable to Sasuke Uchiha's Complete Body - Susanoo in terms of strength thanks to Six Paths Sage Chakra. By using shadow clones, Naruto has shown the ability to combine three Kurama avatars into a single construct with three faces and six arms, which is very similar to the chakra avatar of his ancestor Asura Ōtsutsuki.

Hope that helps

Bej

Thanks for the reply @Dragon. If Naruto went into six path sage mode, then why didn't he show the full bijuu form if he didn't have six path sage mode (ie) before the guy struggled with Madara? If I'm right, he only met Hagoromo during that fight and got the power of six paths. Please correct me if I'm wrong

Dragon

@Bej did he already have full control of Kurama at the time? I can't quite remember because he went to workout with eight tails, then Kurama decided to help Naruto and after that, Naruto started using Kurama's powers properly before just using sage mode and just asking for Kurama's help, if he's desperate or raging please correct me if i'm wrong

Bej

If I remember correctly, Naruto left this turtle island to join the great ninja war after mastering his evil side and also befriending Kurama. He made full use of Kurama when Madara gained the power of six paths.

Dragon

@ Bej was Kurama with the eight fighting tails

Dragon

@Bej also I forgot to mention the six way sage mode is the last mode, Naruto combines normal sage mode and kyuubi mode together, this is also used in the fight with Nagato