Ricoh G188 Service Manual page 152

Image Transfer
There is a rim [A] at each edge of the transfer belt. The ends of all the rollers ([B] for
example) in the transfer belt unit must be between the two rims.
There are two rims (width [C]: about 5 mm) on the underside of the front and
rear edges of the image transfer belt.
This belt must be installed the correct way around. When you reinstall the image
transfer belt unit, install it with the number [A] on the belt at the rear side of the unit.
Put "Lubricant Powder" (B132 9700) on the surface of the image transfer belt [A], while
G188/G189 4-38 SM