Another XS falling on it's face at 6000 rpm

[mjewell]

81 xs400, loud pipes, went up to 147.5 on the mains, bike pulls great, idles perfectly, no flat spots all the way to 6000 while under load. I can coax it to 6500 on a straight or down hill. There are no plastic air boxes around the stock filters, so I'm guessing the way too much air? Did a plug chop plugs are a bit black, not lean looking but not golden either. I'm thinking I throw some pods on there which have a lot less surface area than the stock filters without the boxes. Though

 

[mjewell]

Problem solved. New carb to intake rubbers,
Pod filters instead of clapped out air filters. Runs like a scalded dog small flat spot at 55k. Using 142.5 mains going to shim the needle a tad to help with the flat spot