01 FLHTC with SE one piece slip ons and SE air filter setup. I did not re-jet but I did take the plug out of the idle mixture screw to re-adjust it. If you don't want to buy the SE air, then you could drill a few holes in the back plate outside of the filter area. I do know people who just put on the slipons without any other mods and the bikes run fine but with better sound. I re-adjusted my idle mixture due to the bike was coughing out the carb once in a while telling me it was a tad lean.
If you use the HD touring slipons you'll probably be ok as they are very restrictive compared to other aftermarket pipes.
If you are changing them , you may not be happy with the sound, many are not, I would go and listen to a set on a RK like yours at the dealer, then listen to a set of Vance and Hines, you'll see a big difference.
Rejetting the carb is simple and not expensive, I would also suggest you change the air filter to the SE high flow kit, you'll see a big performance increase and a better running bike.
Harleys come lean from the factory. Adding a free flowing exhaust is going to make the situation worse.If all you do is the mufflers then at least drill the plug for the idle mixture. Go to this website it will walk you through the jetting process. www.nightrider.com
Follow HotRoadKings advice - The biggest performance (read: FUN) bang for your $ you can do to a new bike is to purchace free flowing slip-on mufflers, the SE air kit (uses a K&N air filter) and then rejet to make your bike run right.
Rejeting is easy, and not perminent. I'm not talking about those slide kits etc., your stock carb with $5 worth of jets will make you very happy. If you don't know how I'm sure there's plenty of help in your part of Ohio, most everyone who has ridden HD's for a while could assist.
Might want to start with 48 slow, 195 high, and tweaking the idle air screw out to 2 turns open.
COldrider hit the nail on the head, could not agree more. IT makes an amazing difference and does not hurt fuel economy, but the sound and extra power will make your wrist twist it more.
Stay away from the dyno jet, makes lots of power but be prepared to loose 8-10 mpg.
Thanks to all that replied. I'll try the rejet process in the spring
after my 500 mile service. I'll have to decide which slip ons to use
then. I don't want it loud , but a little more volume would be nice.