Hi folks, just took apart my Bafang BBSHD mid drive and greased the gears after 1,000 miles from a tube of Park Tool bike grease. I put it back together and during my first ride my pedals started to seize and pedaling became quite hard. It clears when I hit the thumb throttle but goes back to hard pedaling a few strokes after I release the throttle. Any suggestions as to the cause would be much appreciated before I take it apart again. This was not an issue before I re-greased it. Thanks!