Topic: CB650 Carb question

[WiredForStereo]

I am not sure if my pipes are stock or aftermarket, they are 4-2 when they should be 4-4.  So they could be from a CB650 instead of a CB650C, but they may be aftermarket.  The thing is that at higher RPMs, like 6 or 7000 it starts cutting out.  I have gone through all the carbs and cleaned them.  Is it possible that they are getting leaned out?  Is there an adjustment I can try or do I have to get new jets?
Thanks

[TwoTired]

Stock air filter?  Is it new?  Clean?
Have you read your spark plug deposits?
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

[cb650]

Year?  Is it supposed to be a custom?



          Terry

[WiredForStereo]

Yes, it is supposed to be a Custom. 1980.
I think I may have figured out the problem.
Someone had mentioned widening the opening into the air filter.  I had two of them, so I said, sure why not and hollowed out the uglier one.  Today I checked the plugs and it seemed to be running a little lean, so I decided to put the unmodified filter cover back on and see how it performed.  It now runs great, I think I may have even gotten rid of the low rpm stutter as well.  I guess the engine just needs that little extra restriction to mix the fuel and air correctly.

[cb650]

Ive never run across this problem but have heard of it.  All my bikes but one have pods anyway.
The one with the air box is the one I'm working on now. Wonder if it will do that.  Didnt when I parked it years ago. Just remembered it does have a k&n filter in it.



               Terry

[byidesign]

I tryed changing the opening on my cb650sc"82"years ago,
     figuring it would "breathe" easier,
     I succeeded in making it hesitate, and run too lean.{especially
       on the low end.
    I ended up going up to #38's on the slo-jets,  lighter springs on the CV slide.
      with a k+n , fine since..{and a few plug check runs later}
       The CV's are really touchy.........
              hope it helps.
                     Bruce