does backfire = lean?

[bloodthirstysystem]

if you're only one size up the pilot from stock you should be able to get a good idle with the mix screw..

 

[marvintheminnow]

i can get a good idle. its the upper and lower midrange that are sloppy. im only one over on the main too. ive got a stock main on the way. the timing was checked and their are no air leaks at my carbs. carbs have been cleaned twice now. This bike is wearing me down!

 

[bloodthirstysystem]

if the idle is set correctly using dead cylinder, worn needles could be the problem - causing a rich mixture.. try dropping them (moving the clip up to the 2nd slot.). could also be a clogged air passage..

 

[marvintheminnow]

needles are brand new. the clip is up one notch. i suppose i could raise it all the way and see what happens.

 

[XSLeo]

You have a new needle. Did it come in a rebuild kit? Often the needles in the rebuild kits are a generic needle. It may work ok in your carbs or it may not.
Do you still have the stock needle? It should be a 4N08. Clip in the #4 slot from the top, is the stock setting.
Your needle jet should be a Z-6.
Try the stock needle, it may work better.

 

[rockdr]

INternal combustion carburation law.
pops in the carb. running too lean.
pops in the pipe running too rich.