Topic: 1972 CB500k jetting

[J-3Driver]

Hello all, I have a 1972 CB500K1 model with 14,000 miles. The bike has an aftermarkt 4-2 exhaust and I've installed a cleanable, reusable foam air filter, otherwise the bike is stock. My bike runs very good but has the classic CB midrange flat spot as you rev it out. My question is has anyone remedied this flat spot issue on their stock bike? I suspect maybe the main jets need to be a size or two smaller. Any input would be much appreciated. Thanks in advanced for your help!

[Deltarider]

You may read this: http://forums.sohc4.net/index.php/topic,7401.msg67251.html#msg67251

[J-3Driver]

Wow, I was looking for a few simple suggestions as to what I could do to help out the flat spot on my stock bike while I have it apart for a new top end gasket set. Now I want to build a world class racer! I have a lot of studying and deciding to do! Thanks for the awesome link, my inner tinkerer thanks you, my wallet and fiancé.... Not so much!