Execute single command with write caching disabled

Whenever I write a large file to a USB drive, write caching makes it very difficult to track process. I can disable it in various ways like echo 1000000 > /proc/sys/vm/dirty_bytes which solves the problem. However then I also have to re-enable the old setting (or reboot). How can I tell my system to bypass the dirty bytes entirely for a single write command? For example, something like:

DIRTYBYTES=nope pv file.bin > /dev/sdb1

Or

pv file.bin | cache_buster > /dev/sdb1

To clarify: The current behavior of pv file.bin > /dev/sdb1 is that the meter shoots to 100% immediately, and then the command hangs waiting for the USB to actually finish writing. Instead, I want to modify the command and make the meter gradually increase at about the correct write rate of the USB drive, **without altering** the dirty bytes etc settings in such a way that the next command will also bypass the cache.