Hi everyone. I own a 2005 Gas Gas TXT280Pro thats making a metallic clinking sound at mid revs upwards in every gear. Is this pinking. I've heard that using a higher octane fuel can help but can anyone advice what the carb settings should be. I.E fuel / air screw etc. I tried to download the user manual but apparently its not available for the 2005 model for whatever reason. I bought the bike second hand so would like to know what the base settings for the carb are in so I know if they've been altered. Advice much appriciated