I've got 3 different rust treatments in garage, I know one of them is really good, never remember which one though so normally end up doing it 3 times as for internal filter, being a £1300 new chinese bike I'm going to take a random guess it dont. ER5 is practically done just been a struggle with time lately, got a screen for it which went on the other week. What tyre was it? I just went with a pilot street on rear for mine. Got to take front wheel off again got the speedo pickup rotated wrong and it's got lugs on it so cant just loosen it and spin it round... typically it was last thing I went to connect! Doing the carb float needles seems to have sorted fueling issue, could have probably got away with a clean but tbh the lack of maintenance on the outside of bike is probably an indication of how well the internals have been looked after so thought may as well replace them for the sake of a few quid. Itching to get it on the road now.