Every few miles I'll get a "Ka-chug" out of my engine rather than a normal power stroke. The machine will balk and then procede normally. It's more associated with lower rpms (2000) in third gear, but not exclusively. Wha-zit?
Don't necessarily disagree with you about lugging under 2500 RPMs but don't believe everything you read in American Iron. I've got every issue they have published of that mag and they have made some really bad statements over the years.
I thought lugging was a bigger problem in the higher gears? I can rap my Dyna at 2000 RPM's in frist it take off so fast it has no time to lug. Now in 4th or 5th lug a chug lug chug. At About 2300 rpm on my bike I get no lugging in any gear from any amount of gas given.
Yeah, I'm not lugging it. A twin should pull in third gear from 2000rpm, no problem. It was described to me as being a "lean condition" meaning that it is jetted too lean (carbed model). But I've got a dynojet 185 in there. ( Scream'n Eagle pformance pipes). At 2000 is the slow(idle) jet still shoot'n? SHould the 45 slow jet be boosted to a 48? Is that it? I should be able to pull third gear at 18-2000 rpm.
2000 rpm's is pretty much it. Lower than that and you truly into a lug area, but as said with a easy roll on the motor will/should pick up. I get down to 40 MPH or 1900-2000 rpms in 5th and that will deffinetly lug there if I was to rap it. I ran a 48 slow with my basic stage one and it realy helped the low-mid range.
You may be in the transition range from low speed jet to the needle. Do you know how the needle is set? If you've got a Dynajet kit in there, the needle has slots for adjustability. How is the mixture screw set?