the USMLE step 2 is taken after most, if not all, core clinical rotations are finished. most people take about a year to finish the cores. thus, you can take step 2 at that time...up until you graduate (ross requires it for graduation). there is a lot of leeway there...thus, there is indeed time to study for them.

most people say that step 2 takes less time to prepare for than step 1. the running joke is: for step 1, study 2 months...for step 2, study 2 weeks...for step 3, bring a number 2 pencil.

because there is alot of leeway, there isnt a specified time to take it. many residency programs dont ask to see the step 2 score at the time of interview. in fact, i know of many, many US grads who actually took step 2 AFTER their last day of classes their senior year (thus, they matched without step2)! of course, they all needed to eventually pass step 2 soon after in order to graduate with the class and start residency later that summer.