...i like them, and I am thinking about installing a set of 4 inch slip-ons.

I have a K&N filter on the stock air cleaner and I was wondering if I will need to put a Tune into the bike to make it work, or will the stock settings suffice.

 

You wont need a tune for that.Mine did fine.

 

More air and no retune??

 

Its not that much more air, the stock air filter flows pretty well as is. And the bike has sensors, it will accommodate.

 

Might I see a noticeable power change?

 

Doubtful.

 

Rineharts might rob your low end torque, but they sound good.

 

Isn't that there claim to fame? Look and sound good and destroy low end.

And at a min get the HD junk tuner/cables and dump one of there maps on it. Then do some of there painful auto tunes. With K&N and slips yeah a slight tune should be done.

 

Hmmmm ...... I do like my bottom end torque. This requires a rethink.

For low end power what might be a better choice? Just Stay stock??

 

Truly I dont think you'll notice it. Mostly your choice of header will have more impact on low end torque.