My Outsider is to slow

I have the Japanese version of Sanyo M-GT7 "The Outsider" - the MR-U4M "Marine Sports"



Everything works, only the tape speed is to slow. Does anybody know, if there is a screw or a variable resistor that I can turn to adjust it? Or does someone have the service manual for M-GT7?

Thanks

OK, found it by myself. There is a screw on the motor, that can be turned. To the right - faster, to the left slower.

I like how the speaker trims look like little racing tires with white lettering.