Ricoh CL7300 with SC201.
Due to the age of the machine, it is very likely that the polygon motor is defective. Either the bearing or the electronics for the motor.
The polygon motor is a motor that has a many sided mirror mounted on top of it... a polygon mirror. In this machine, it is two mirrors placed on top of each other. The motors job is to spinn the missors fast and at a steady speed. Several thousand RPMs.
The lasers in the machine is aimed at the mirrors. As the mirrors turn, the laser beams are spread out and go through several lenses and mirrors in order to be able to swipe the length of the drum, and make a latent electrostatic image - that is the key to how a laser copier/printer works.
When the motor is not able to spinn this mirror fast enough due to a worn out bearing (or a defective driver circuit on the PCB that the motor is mounted on) the machine shows an error code.
It must then be replaced.
I've included a few pictures, so it's easier to see.
This shows you basically where the laser housing is located. The polygon mirror motor is inside this houseing. Make sure it is clean inside.
This shows how the lasers hits the two mirrors and some of the path it taked before it svipes the lengt of the drums.
This showes how one mirror is placed on top of the other - and how the laser beams (2) hit each mirror. It is one laser beam for each color in this model.
This shows how you take out the polygon mirror motor, and where it is located inside the laser houseing. Keep it clean.
This is a part that may be better it a technician do the job. If not, get the proper procedure as it requires several steps in service mode for adjustments, calibrations and so on.
It is a fairly quick job for a technician to do. And an easy way to destory the machine for people who does not know what to to.
So make sure you get the proper documentation if you're going to replace it yourself. I'm not saying it is hard - you just have to do it the right way.