Mon Nedarim 64

There is a Machlokes between R Eliezer that hold that one may regret his Neder for Kavod Av (that it reflects bad on his parents) and the Chachumim disagree.

R' Tzadok says they would argue even regretting for Kavod Hashem (Ran in the name of Sifri: that it is like you made an oath in his name.) The Chachumim says that R' Eliezer would agree that you can't. Abaya says since you might say you regretted because of Kavod Hashem when you didn't, since you're embarrassed to say that you truly didn't care about his Kavod.)

Ran explains that the argument between the rabanan and R' Eliezer if you may lie for Kavod Av, or since it's not as bad as Kavod Hashem he doesn't care if he tells the truth.

Rava explains since all nedarim could be knocked off with such a claim, he might not go to get his Neder Matir, since he'll thinks it will be automatically Mutur.

Ran says but by Kivod Av they argue if it would automatically be a good regret for all Nedarim, or there are small Nedarim that wouldn't reflect too badly on the parents that he made it.

Alternatively, the Rava holds like Abaya by Kivod Hashem, that we're afraid that he'll lie. However, he disagrees completely that we would be worried for this by Kivod Av, since no one would be too embarrassed to say he doesn't care about their kavod. So therefore he needs a new reason why the rabanan says you cannot regret for their kavod. So we must say that the Chachamim has this new Chashas that all Nedarim could be Matir with this, so they won't bother having them Matir. R' Eliezer is not worried for that to happen.