The MRP Solid roller does not have a groove in the center for the chain. It is used in different circumstances to standard set-ups.
- First: if the crank and chain line is such that the grooved roller will not line up on the chain no matter whether the thin flange or thick flange are to the boomerang. The customer can use the solid roller (or sometimes called the flat roller) on the top to roller position to have the system run smoothly.
- Second: if the customer feels that they need more tension on the chain, they can run the solid roller on the bottom roller position for more tension.
The MRP Solid PU roller is equipped with cartridge bearings.