So i have an 81 cm 400t that i love! But I’m not getting the her i right power out of it. I’m maxing out at about 70mph with 9500 rpm. I thought it was a vacuum leak but bought wd40 and sprayed around the carbs and boots but there wasn’t an rpm change like it should when there is a vacuum leak. I know my carb needs a little tuning for the backfire but it’s close. Is there another’s spot i need to check for vacuum leaks? Or what could be getting me such low power? I’ve heard they are supposed to get up to 90mph. Do i need new jets? Or should i try new boots? Or what’s going on?