and

I won't bother to go


My reading.

I've put "I am" rather than "I'm" because in the second example I imagine the person stressing "am", to mark the contrast with the other person saying he/she's not going.

You might well think "pegar" suggests something arduous or unwelcome, but "pegarse" really doesn't carry that sense inherently; it's just a familiar or colloquial way of saying "darse" or "tomarse", with the same basic meaning. It can be positive, negative or neutral:

pegarse una ducha
pegarse unas vacaciones, etc.

Here's an example to illustrate how "pegarse el viaje", in a different context, can have quite different connotations:

"Lo que si he decidido ha sido seguir ahorrando de cara al verano que viene y así pegarme el viaje de mi vida"
http://foros.vogue.es/viewtopic.php?f=6&t=190357&start=100

In your first example you can quite imagine the person saying something like "I can't be bothered to go", and "pegarse el viaje" certainly can imply something laborious, but that sense comes from the context, not from "pegarse" itself.

Just as I'm about to post this I see that Simon has suggested it, but I'll go ahead anyway because you may find a bit of explanation useful.

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Note added at 1 hr (2013-04-15 09:23:02 GMT)
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What I'm saying is that "no me voy a pegar el viaje" means the same as "no me voy a dar el viaje". "Pegar" is not being used here in the sense it has in "no me voy a pegar una paliza". The thing is that in the negative it will usually be said in cases where the person really doesn't fancy going and/or doesn't think it will be worth it.

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Note added at 4 hrs (2013-04-15 12:47:22 GMT)
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Backtracking slightly and on further consideration (and consultation with a native speaker at home), the negative form, "no me voy a pegar el viaje", does imply that going would be an effort, and not worth it, so I think "I'm not going to bother going" or "I can't be bothered to make the trip" would be quite suitable translations. However, the reply, "me voy a pegar yo el viaje", carries no such implication. It just means "I am going to go" or "I am going to make the trip".

With all due respect, the earlier suggestions are too formal given the context. In American English, "schlep" would be a more suitable colloquial option.

Just my two cents.

español term (edited): no me voy a pegar el viaje / me voy a pegar yo el viaje

I don't see why it needs anything more that this:

"...y no me voy a pegar el viaje" = "...so I'm not going"
"...me voy a pegar yo el viaje" = "...so I'll go"

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Hope this helps



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Note added at 14 hrs (2013-04-15 23:11:23 GMT)
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Seems the most natural solution to me anyway... Given teh context.