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This seems to have been more confusing that it was intended. So a quick explanation.. the V4 motor takes at least 2.5 hours after running at full temperature for the oil sight glass to give an accurate level reading, so we leave the bike to settle while the service is complete and customer has his coffee or takes a demo bike for a ride and we carry out the other service items, then check the level. If it's OK then we remove the oil, which can take an hour to drain fully. then replace it with the same amount (in kgs, so we are not comparing volumes of warm vs cold and not pouring hot oil about in measuring jugs). Then run the bike to temperature and we know the level is correct. it's the simplest and safest way to know without waiting another 2.5 hours. Ducati suggest this procedure to ensure the bike isn't over filled and all dealers will be doing this. We thought it would be interesting to see.