Originally Posted by 6677

I did work experience at school with Titan motorsport. They make car performance parts and when i was there i found that normally its the other way round. The system will run better after being run not when brand new because there are machining tolerances when things are made. When the parts are assembled they may be 0.1mm too big which may not seem like alot of difference but with car parts and all the tolerances adding up it can be quite a difference. When the parts are run a couple of hundred revs such as when you start the engine the parts will wear themselves out and fit perfectly and run smoother. Perhaps on this smaller scale they dont wear and run in properly compared to full size cars and almost jam up a bit. I dont know much about mini racing but maybe if you continue to run your rougher diffs they might smooth out again as they wear down.