Hi, I would say not worth the hassle. There's the obligatory 90 minute delay landing at JFK, then you have to clear customs, grab your bags for recheck before you can even leave. Thats a busy international arrival slot so you might be in line awhile.
Add to that the fact that JFK to NYC takes an hour or more at the best of times, I'm afraid you won't make it.
Sorry.
-M
Hassle