i bought a gt200 a couple of year ago. bought it with 1600 miles after an oil change and air filter cleaning had just been done on it. i am now over 4000 miles, so i thought i would change the oil and air filter this spring. oil change went fine. when i was taking out the air filter, the one currently existing in the gt200 is quite different from the new stock one i bought. attached picture shows the new stock air filter (bottom) and the existing one in the gt200 (top). does this look like an off-brand or modified version? it also does not seem to be oiled at all, but appears to still be in good shape and fairly clean. should i just clean and re-oil this existing filter or replace it with the new stock filter? thanks.