I just bought this motor pololu.com/catalog/product/2271 in the webpage it says its no-load speed is 1010 rpm. However, when I run it at 6V it only reaches about 500 rpm. Even getting rid of the gearbox is not going to make it go much faster. Of course, if I run it at 12V it will reach 1000 rpm but I don’t want to damage it. Am I doing something wrong? Is the no-load speed wrong? Can I run it for a long time at more than 6V?