Sharp JC-AV1 Plays too fast!

Hi! Does anyone have a service manual for this model, or know how to adjust the tape speed? Mine works fine apart from it plays tapes too fast, so if I can find the motor speed adjustment, I can slow it down a bit!

Thanks in advance

Have a look for the adjuster on the motor top, which will be a small screw hole with a variable resistor inside.
Failing that, try change the belts for better/tighter belts to provide a bit more resistance to the motor than the current one which may be loose/worn.

If the pinch roller tension is too loose, or if the roller surface has become glazed and no longer rubbery, it won’t grip properly & allow tape to slip in which case, will play too fast. Remember, the capstan needle is the actual speed calibrated part so the pinch roller needs to do its part to ensure the tape follows the actual speed of the needle.