I'm seriously lost about something. I remember that some chapters ago, Kyubi (and maybe Hachibi too) had ''no more'' chakra because Naruto (or Bee) used too much and they had to ''recharge''. I don't remember when and I don't want to go search in all these pointless battles episodes... =.= But I'm sure you saw it too and maybe asked yourself the same question: HOW COME!!! Aren't they like: Eternal chakra sources or something? They are creatures of chakra! How can they be out of it! And recently, in the new episodes, Naruto is like overusing chackra to protect all his ''friends'' and it looks like it's doing no shit to Kyubi! Wtf? Can someone explain?

Variety's the very spice of life, That gives it all its flavor. -- William Cowper

Yes indeed Naruto's fusion with Kurama ended up depleting all of Kurama's chakra. However he asked for some time to get recharged, did so and then shared a bit with his companions.
The Bijuus might be an eternal source of chakra but it certainly does not mean that they have infinite chakra, that's why we don't see Bijuudamas being fired like SMG rounds. Even more, 7 Bijuu were defeated...

Hope you find this usefull.

Chayto

"Spread your ear-pollution both far and wide" - Billy Squier, The Stroke.

not sure... =S

So you said Naruto fused with Kurama and that took all his chackra? I'm not sure remembering that. =/ And I don't remember what for. Do you have the episode? Or more information?

In episode 629 it's vanishing too (the protection) My theory is that Naruto is worn out and can't control all that, not that Kurama is getting low on chakra. For that, am I right?

For me eternal means infinite! xD But I guess you're right, even bijus may have limits. =/

It's not the 7 bijus who were defeated, it's their jinchuuriki.

Thanks!

-Pumpkin-

Variety's the very spice of life, That gives it all its flavor. -- William Cowper

Naruto Ch. 611 you can see Kurama asking for some time in order to regain chakra, same as the Hachibi and then is said by Obito who realizes this too.
I'm guessing that by Ch. 629 he is seriously worn out, both him and Kurama. I don't think that he cannot control the chakra since they fused and now Kurama's chakra is Naruto's one.
At least when Hidan and Kakuzu defeated the Two Tailed Bijuu she transformed into it, and I think that it means they defeated the Bijuu.

"Spread your ear-pollution both far and wide" - Billy Squier, The Stroke.

I think they are creature of chakra with eternal source of chakra, but that doesnt mean it could out charge.
Its like this : they have a glass of chakra, they could get refill when the glass is empty, but the problem is, to refill that glass, they need time (to recharge it).
so Naruto is using the chakra in the glass, its like there's a hole under the glass, the refilling/recharging time of the glass take longer then the use of it.
Maybe the same could be applied to the Biju, but the glass that the biju have is not glass. Its a very big drum/barrel.Maybe thats an appropriate comparison.