The best motocross oil is racing oil by Red Line (USA). It's fully synthetic, high-performance oil, which not only protects two-stroke engines but also significantly increases their power. According to numerous tests, engine power increases by 3-5%. The excellent detergent properties of this synthetic oil and its stability allow extreme engine loads. The Red Line oil can be diluted or used in oil injection systems. An optimal dilution ratio is 50/1, although, in some cases, a 100/1 ratio makes sense. For this reason, when traveling on rough terrains or at high engine loads, it's worth choosing an oil from this manufacturer.