I updated successfully my RICOH RW8160 To RW8165 form 2.4x +r to 4x +r.
You need the Firmware for both of the drives and the Ricoh flasher (Rflash)
Extract both Firmware to separate Folders cut and paste the Firmware for the RW8160 to the same folder of RFLASH. Start the Flasher and you will see the Drive (RICOH RW8160 + The Firmware) inside the Flasher Folder… Now press NEXT…Attention… Don’t Press …START…Now go to the Folder where you extracted the Firmware for the RW8165 and change its name from ((M62_0103.RIC)) to ((M61_0108.RIC)) and paste it to the same Folder of the FLASHER and overwrite the other Firmware with the same name and a different size in this Folder… Now go to the FLASHER and press …START… When the FLASHER is Finished, reboot your Notebook and you will have a new RW8165.
Please try this on your own risk.