Join Date: Aug 2008
Location: Monroe, Louisiana
Welcome to the forum. The "oil filter" is nothing more than a large mesh metal screen for keeping chunks of metal from getting into and damaging the oil pump. If you have the right side case removed, by all means check and see if there might be anything obstructing the filter mesh. Otherwise, don't worry about it.
I'm sure you discovered it's much cheaper to change the oil yourself. Most members here change the oil every 1,000 - 1,500 miles. Why Hoinda recommends a 4,000 mile oil change for an air cooled bike with no oil filter is beyond me. Frequent oil changes are what prolongs engine life. In case you weren't aware, it takes 1.6 quarts of oil, and the level is checked with the bike upright (not on side stand) and the dipstick unscrewed and just resting on the theads. Putting in too much oil can cause crankcase pressure to increase to the point it blows out the left side oil seal.