Shimano Disc Brake Service Bulletin


Important Product Bulletin


Shimano has recently learned of a potential quality issue riders may encounter using the model BR-M485 disc brake calipers. Shimano received some calls regarding concerns over traces of oil found on new caliper bodies. Please note the following information and procedures regarding this issue.

Mineral oil on BR-M485 calipers
1. After investigating this issue, Shimano found that in most cases the calipers were not actually leaking oil. In these cases, residual oils were trapped inside the two halves of the caliper body. If the caliper was assembled with some residual oils trapped inside, a very small amount of this trapped oil may continue to seep out from the joint when the lever is squeezed during initial usage until the oil completely dries out (see photos below of the detailed areas).

2. If you see traces of oil on the caliper body, you should also check the brake pads and rotors for oil contamination. If the pads are contaminated, you may experience some noise and poor braking power. If the pads are contaminated with oil, clean the caliper and replace the brake pads. If the rotor is also contaminated with oil, wipe it off with a clean rag using rubbing alcohol.
Please contact us or Shimano for free replacement brake pads.

BR-M485 caliper with actual leakage
Although most cases are due to residual oils, there may be cases of actual leakage (estimated to be less than 2%). In the case of an actual leakage, oil will continuously flow out when the lever is squeezed. If this is the case, please stop riding the bicycle and bring it in for us to evaluate and replace the caliper, which Shimano will supply. Or, you may contact Shimano for one.

Oil Sweating

     Please inspect closely and ask us if you have any questions.

If you notice any oil on the calipers in the marked areas (see photos), this does not necessarily mean that the brake is leaking. There is an O-ring seal between the two halves of the caliper. When the brake is assembled, there may be oil between these two halves. This oil is pressed out when the brake is operated the first time. The oil will soon stop emerging.

Please take the following steps:
- Wipe the oil from the caliper, while pulling the brake lever.
- Check that there is no oil on the brake pads. Replace the pads if necessary.

Should you have any questions or concerns regarding this issue, please call us or Shimano's service line for assistance at Shimano American 800-423-2420.