i’m recently took delivery of a new Genesis Core 50 2011 with SLX brakes with 180 / 160mm discs. So far i’m pretty underwhelmed with them as there is very slight run when riding (no resistance but still an annoying noise) and more improtantly there have been a few instances under heavy prolonged braking that the a sudden and very noticeable vibrating feeling come back through the lever and loss of braking power?

Is there anyhting i can try to improve the performance of the brakes?

To stop the brakes dragging you need to re-centre the brakes on the disc. This may also stop the vibrating as it may be caused by misalignment.