Finding tempo while sampling/ loop

Hey just finally getting a hang of things with this sampling stuff. I was wondering when I am sampling vinyl often times I get a nice loop but its not an even number of bars say a 2 or 4 but like a 3 bar loop. How do you guys go about this while doing your chops. In addition, I know this may sound very novice like but how do you count your bars with different sample at different tempos. Is there a way for me to practice counting bars etc.. Many thanks!

how do you get a 3 bar loop? any examples of songs you sampled that would give you a 3 bar loop? i guess with songs that are a different time sig, but still i just wanna hear an example.

maybe you could solve that by not looping. chop the sample up into pieces so you can arrange them in a way that gives you 4 bars instead of the 3. play around with the chops and find a way that works.