Thanks guys, some great suggestions.

Quote Originally Posted by piu58 View Post
35 mm film has 120 Ám, 120 film 100Ám thickness. Some companies make both from the same base. It may be that you have 120 Ám MF or 100Ám 35mm film.
Hm. Makes sense.

Quote Originally Posted by Douglas Fairbank View Post
The one bit of advice I would always give was to try to always use the same brand take up spool as the film being used. If the backing paper edge gets gets stressed due to the spool being too narrow or the film not running on to it in perfect alignment this can have a big effect of the force needed to transport the film.
I never even considered that the spools could be the issue. I was definitely mixing and matching spools (400H or Porta) when I ran into problems. I'll run the next roll through with a Foma spool and see if it helps.