I've got 2 Jitterbugs. 1 black one in 1/4oz, and 1 double jointed frog colored one in 3/8oz. Both bought from different stores at different times. 

 

When retrieving either one of them, they don't move side to side evenly through the water like they're supposed to. They both retrieve to one side or the other and have no wobble. Inspecting them, they don't appear to have defects. When they get back to me, they don't have grass or weeds or anything on them, so they aren't getting caught in stuff that makes them do this. I fish them on mono. I just don't get it.

Glaucus have used jitterbugs quite a bit over the years for night fishing. You might try carefully bending the lip to get them to run straight. Also, the line tie could be in the wrong position when you start retreiving. I don't know how old yours are, but the best jitterbugs are the older American made ones.. The newer import models have a thinner, cheaper lip, and don't always run true.

Light line also helps the small one no more then 10lb the bigger one 12 is fine...

1 hour ago, Maxximus Redneckus said:

Light line also helps the small one no more then 10lb the bigger one 12 is fine...

8lb mono or 15lb braid is all they get used on for me, so no issue there. Definitely not a line problem.

Usually, that's from fishing them too fast.

Have not fished the a Jitterbug that's newer then 25 years, mine are vintage wooden musky models and 60's vintage plastic 3/8 models.

Jitterbugs have fixed hook hangers that tend to be too tight locking the treble hooks and that acts like a keel, the hooks must move freely.  The line tie can also be bent and not move freely, so some tunning is needed.

Jitterbugs should be retrieved slowly to do their thing.

Tom

Old ones are very different from new ones.  I replace the hooks and put split rings with shorter trebles. I bought a new one and it won't float.

They like a slower tip as well. Rods are stiffer than they were years ago when that bait was more popular.