I have a 06 RK, I just put in s&s 551 cams, af, dual rush pipes with rush 1-3/4 baffle mufflers. I did not use a turner, but had the bike dyno'd and flash tuned (I think that was what u call it) I am now happy with the power but not the sound.
I am now wondering what will happen if I put the stock mufflers back on without putting it back on the dyno. Will it still run ok even if not at max performance? Will it run to lean or rich?

 

Putting on the stock mufflers after doing that level of stage 2 work will definitely affect the air/fuel ratio and emissions. Whether or not it will hurt your motor over time, I'm not entirely sure. But it would more than likely run rich and I would expect more carbon build up. Also, it will not run as powerfully or smooth as it does now. Your best bet is to get yourself a set of quieter mufflers that are made to handle the air/fuel trio you are already using. I would suggest some vance and hines slip ons. Their monster rounds and hi output slip ons are pretty loud but they have some quieter options that still look great and let you keep your performance! Just some thoughts from your friends here at WanaRyd Motorcycle! If you have any questions feel free to give us a call!!!!!

 

If you put the more restrictive DOT approved mufflers on then you really should get the bike dyno'd and flash tuned again. You could also get your own flash tuner. Some modern tuners can "Self-Calibrate" so you don't need much know how. You can also store different tuner maps so you can easily switch setups for atmospheric conditions or temporary performance accessory changes.

 

I would give Rush a call. There are different baffle options that may get you where you want. This in my opinion is the best place to start before you spend the money on new exhaust.

 

Super Trapp or fuelmoto both make disk type slip on that will allow for dB adjustment. I have the SE fatshotz made by super Trapp and they are not much louder than the stock pipes but perform.