Sure!
In this sentence particularly, it is just because the idiom/collocation "conocer sus propios lÃmites" exist. In fact, I've just edited it again to change it into plural. It could have been "sé cuáles son mis lÃmites", "sé dónde empiezan mis lÃmites" too.
Generally speaking, it's not easy to stablish the difference between "saber" and "conocer", but I think that the trick which can help most of times is that usually "aprender" or "enterarse" can be used in the same situation that "saber". Otherwise, the most suitable verb will be probably "conocer".
- Sé inglés. Lo he aprendido en los últimos años.
- Sé que te vas a Francia, me enteré ayer por un amigo.
But:
- Sé* a Pedro. Lo aprendo* desde hace dos semanas
Unfortunately, there are other examples which don't fit with this rule...
Maybe this link can help you
http://www.aulahispanica.com/node/121
P.S. Just wondering... I've come up with a personal theory lol. "Sé" may be used when, as I said above, the complement can be used with "aprender", and when "sé"="conozco la siguiente información:"
That's surely why "sé mis lÃmites" is not correct: "conozco la siguiente información: mis lÃmites".
But "sé cuáles son mis lÃmites" = "conozco la siguiente información: cuáles son mis lÃmites".
Perhaps I have just confused it even more lol
CC: lilian canale