"The role of the lubricant, as far as we can tell, is to take up space so that dirt doesn't get into the chain," Spicer says. "The lubricant is essentially a clean substance that fills up the spaces so that dirt doesn't get into the critical portions of the chain where the parts are very tightly meshed. But in lab conditions, where there is no dirt, it makes no difference. On the road, we believe the lubricant mostly assumes the role of keeping out dirt, which could very well affect friction in the drive train."