If your XR has a dry sump with the oil in the frame reservoir, you have to check it consistently every time. A long time XR owner taught me to start it, let it idle for ~ 3 minutes without reving it up, then kill it. Check the oil level immediately. I have gotten excellent results in this manner. The oil in the frame drains down to the engine over time, so this is the only way to get a true reading. If you are overfilling, it may be blowing the oil out of the case breather as you ride.:D