The specs listed on the site (and elsewhere) says to use 4L of oil with filter change for a 1999 Drifter but the Owner's Manual has 3.1L when filter is removed.
Which is correct/recommended. 4L seems to be towards the top of the fill area but not over. Should I drain 1/2L out?
Thanks.
I always end up using a little bit less then 4 quarts with a full draining from the oil screen plug and a filter change. I fill the filter and install (a bit messy, so be quick about it), then level the bike and add oil until it's a little over where I want it in the window. Going a little over makes up for what was spilled when putting the filter on. Now fire the bike and let it run for a minute or two. Shut it off and wait 5 minutes and check the oil level with the bike leveled. You should be good!
The Manual and on a decal near the filler plug state:
2,9 L with same filter.
3,1 L with new filter.
3,5 L to begin with ("dry engine").
With a new filter element fill the filter as far as you dare.
Good rule of thumb is: refill with same amount of fluid that is to be discarded.
To much oil can be sucked into the carter vent. Too much oil can be turned into foam by the crankshaft, being hit too violently, this air present in the oil to large amounts may lead to issues with overheating.
How can one compensate in the window (to be seen with a mirror on a slightly bent stick, like the back of a dish washing brush or something) for what was spilled? Halfway the inspection glass is always where the oil level should be.
3.1 is good for all years with a filter change. The oil level in the sight gage should always be used, not any specific amount. You should run the bike a bit to get the filter filled and then with the bike level, wait 5 min, and it should be between the high and low marks... middle to top. Personally I have always allow mine to go towards the top. As long as you can see the level (above middle), with the bike rested at level, you are fine.