Carbs.

[Seacat]

Grumble, grumble.

My bike, a 1981 CB750C is losing number four Cyl. at lower RPM's. It just isn't firing. At higher RPM's it's firing just fine.

This leads me to believe that the carbs are the problem. (I'm getting spark at idle.)

So tomorrow I'll be pulling the carbs. This should be fun.

Cat

[CB750Winger]

  Could be a plugged slow jet. Take the float bowl off #4 and you should be able to get to the jets. The slow jet has a very small hole so make sure it is clear. Does'nt sound too serious.