It is a painful experience for all us administrators to truncate logs regularly. I just created a job to execute
sp_msforeachdb "use ?; backup log ? with truncate_only ; dbcc shrinkfile(2,5)"
on all the servers at frequent intervals. It has saved me a lot of time. hope it helps you too.
n.b: I assume that file id 2 is the log.(change it as per your installations)
When doing bulk data changes it may be beneficial to disable indexes prior to starting the operation. Fortunately, SQL's rich metadata makes this very easy to automate in a robust fashion.