JVC HR-S7000U rewind keeps stopping early?
 

I have a JVC HR-S7000u when rewinding a tape it would stop early in the beginning will go 1/4 of the way then with each retry would stop after a few seconds but with the right side hole on the tape for the light sensor covered it will sometimes make it all the way to the beginning but sometimes still stops short where after a few tries will finish ..I have already replaced the belts and idler tire. The reels have plenty of torque .

That's an ancient JVC, and not one suggested for ... well, anything.
Late 80s, maybe early 90s.
It's a museum piece, not anything for quality transfer, not really even safe for watch or rewind.

Unfortunately all VCRs are museum pieces and anything you buy are the same even refurbished ones like refurbished so I just want to fix it .

If you don't know how to fix it yourself just get a cassette rewinder, There is nothing we can do to help you other than just guesses, Possible causes worn or stretched belts, worn clutch pads (if it has them), faulty cassette ... just to name few guesses.