Why didn't Naruto summon Chief Toad when he fought Sasuke In Final Valley?

That... actually probably would've been a good idea. I guess he just didn't think of it.

Naruto probably reasoned that if he had summoned Gamabunta he would have to take time explaining the situation to him and then take more time convincing him to help out. Since he wanted to bring Sasuke back as soon as possible, he most likely didn't want to risk giving him any opportunity to get away. This affair was between two best friends and teammates, so Naruto must've also realized that it wouldn't be right to drag the Chief Toad into a fight where his giant belly could be pierced by an oncoming lightning-covered arm.

Let's Clear up Some Stuff: (ahem)

a) Gamabunta would probably have some Water jutsu that would only harm Sasuke, Gamabunta shows that he has multiple jutsus, and if this weren't true, Naruto could transform Gamabunta to a smaller toad (or anyhing just as long as it's small), so that in that form he could damage to Sasuke without killing him.

b) Gamabunta would have helped Naruto, because he knew the story of Orochimaru, and he would have wanted to avoid Sasuke from going the same path.

c) Camon dude, Sasuke would have done nothing against Gamabunta, he has what, the powers of Kakashi in his 2nd Level Cursed Seal State, camon, so what he can face Shukaku and Kuruma, but he can't face Sasuke, and what is Sasuke going to use Genjustu to control/stop Gamabunta, no he is not, because HE CAN'T, just because you read from a stone and have a nice pair of eyes that does not mean you know Genjuntsu, it means you are able to use it, like if you train for it, not just plot convenience, Sharingan gives vision of the moves you are going to make (i.e punches and stuffs like that), so it is a natural boost in Taijutsu, but in terms of Genjutsu, it helps but only if you practise for it.

In the end, Sasuke should have stoped Naruto's summon, like breaking his contract with Gamabunta or something, and making it so when Jiraya goes with Naruto for 3 years, he signs the contract again, that would have made some sence but this is ridiculous, almost as bad as Tobi's excuse for wanting to bring the Juubi in perfect form.

Gamabunta wouldn't have helped Naruto defeat Sasuke. Fighting Sasuke would of been a waste of time for Gamabunta because Sasuke at that point of the story was a small fry plus Naruto at that time couldn't control Gamabunta. Gamabunta would of only helped if Sasuke at that point in the story was able to summon Orochimaru's purple snake. Gamabunta loves going head to head with Orochimaru's purple snake.

The simple answer is that it is a huge plot hole. There is no logical reason why Naruto wouldn't summon Gamabunta to bring Sasuke back other than Kishimoto (the author) didn't want it that way. Naruto promise Sakura that he'd bring him back no matter what. There are lots of plot holes in Naruto. Its best not tot pick them apart.

It wouldnt have led to their current character development. Gamabunta n Naruto would have likely defeated sasuke, but then what? It would have been difficult for Bunta's big hands to strike sasuke, but oh well. There one on one battle was to be a reminesient of the battle of Madara vs. Harishiama

sasuke and naruto's battle was an emotional one , naruto didn't want to bring him back through force but he wanted to persuade him , bringing out the toad would mean that naruto has given up and lost faith in his own ability to bring back sasuke , every time naruto had the chance he would talk to sasuke rather than fight him , also you have to understand they were both pretty fast , there were little opportunities for them to catch a breathe since they were both fighting seriously .

however the main reason is bringing the toad will create a plot hole since sasuke will be captured to say the least which won't allow him to go to orochimaru and if he does escape , then how will it be explained that the chief toad who fought shukaku was able to let sasuke go .

The best answer is the correct one. I am 14 and have fought kids bigger than me and I used the in and out method because I knew from my cousins that are UFC trained that taught me stuff also taught me how to use this method this guy knows what he's talking about and never ever doubt it because if you ask any professional fighter they will tell you the exact same thing for fighting a bigger opponent

Well.. It would be silly actually... From my understanding... Bunta is usually brought out when there's a need to fight an extremely large enemy.. Like the tailed beasts or Manda. It would be pointless to bring him out against Sasuke.. It wouldn't be a fair fight anyway... I don't think Sasuke could do summonings at that time... and they had to fight as equals...

His useful for fighting big enemies, it wouldnt have made a good story line if he did.