Can any of you Banshee owners tell me about any after market mods to get better low end power out of a Banshee?

 

A 2into1 pipe will do the job. Dynoport is the most extreme (2 into 1 headpipe), while you can get Paul Turner midrange, FMF gnarly or DMC, if you don't want to loose too much top end.
More compression helps, as well as reed spacers...and let's not talk about big bore or even better, power valves.

 

As mentioned....A 2 into one pipe set will work.
Even easier is dropping a tooth on the front sprocket. You will not loose much on the top end.
Another thing would be to increase the compression with the likes of a cool head with interchangeable domes. Or mill the head for a less costly method.
Some of the stumble off the line can be cleaned up with a new pilot jet. Which again, is very cheap to do.
It depends on how much you really want to spend.

 

Single carbed mine and it seems fine, lower front sprocket tooth (12-13), pipes are always fun too.