Got the 21 back after having the main bearings replaced and the carbs sonic cleaned. All standard jetting running 128 mains and it seems to be running too rich. Removed the air filter and it ran a little better. Then done the wire splice and seemed to run better again. Does this seem right, i want to run it with the filter so should i start coming down on the mains or could it be something else. The rest of the bike is standard. Any help gratefully appreciated. Ive had the bugger since July last year and have yet to have it running right..