Join Date: Apr 2014
Location: Perth, Western Australia
As succinctly put in Wiki:
The goal of modern engine break-ins is the settling of piston rings into an engine's cylinder wall. A cylinder wall is not perfectly smooth but has a deliberate slight roughness to help oil adhesion. As the engine is powered up, the piston rings between the pistons and cylinder wall will begin to seal against the wall's small ridges.
Operating the bike on a light throttle actually prevents the effective sealing of the new rings and barrel.
The manufacturer's line is unchanged from the days of cast iron liners and rings, and the lower grade plain bearings used in the past.
What they should really be saying, but won't, is: 'operate your bike gently and at low speeds so that you familiarize yourself with the bike, don't become another road accident statistic, or a potential litigant against us'.