I have a 2011 FLHTK.
I drilled out the cat on a header pipe I got on eBay.
I put the Rinehart 4" slip ons on and its ok but hardly enough thump.
What I'm thinking of doing is this.
Taking stock header decatted off and having the left side muffler port welded shut. So basically I will have a 2 into 1 system.
This with using only the right side 4" rinehart muffler. Hoping to increase toque and sound.
Has anyone tried this? Or knows of anyone who tried this?
Thank you.

 

Man..... I wish I had an answer, I wanted to use a stock 2010 2 into 1 and one of my twin slash mufflers! I bought a 2 into 1 anyways because I couldn't find an answer to this same question...... Didn't want to do it in fear of messing up my motor. I'm pretty certain you could do it, and everything would be just fine, just didn't have the ***** to do it, plus it would have been much cheaper.

 

There's a post on this very subject buried in the DIY tips and tricks thread.I see no reason why it wouldn't work but you may have to experiment with the baffle size to get the sound/backpressure you want.I have an extra stock header I've been thinking of doing the same thing with just to eliminate cleaning the left side muffler.update; its not buried too deep it's the first one

 

Sure ya can do it but it cuts the exhaust flow in half. Kind'a different then a real 2-1.

 

Rinehart sells competition baffles which are said to be much louder than the standard baffles. You might try these and see if it is loud enough before welding shut one side.

 

The stock header on the 09 and later bikes is a two into one all the way up to the end of the collector where the cross over is.I don't think you'd be doubling back pressure just blocking off the cross-over unless you were still using the stock muffler.If you have a stock muffler with the baffle removed you'll notice the end opening is about twice the size of the stock baffle and roughly the same size as a two into one muffler.If you already have an extra stock head pipe laying around you won't be out much $ to try it.

 

I stuffed a rag into the left on my 13 limited with 4" rineharts , and the cat removed. the sound changed completely. It sucked, no resonance at all.

 

FWIW, about 80% of the exhaust exits out the right side on a stock system. Many have successfully closed off the left pipe completely for various reasons and had good results.

 

You cant do that. I dont know how much people realize this but building an exhaust system is an art and a science. an exhaust is just not a pipe bent to follow the lines of the bike. On a single sided exhaust u will notice that the diameter of the muffler is bigger than the 2 muffler system. there is a reason for this. Its all about flow and exhaust waves. Ask a guy like Jamie at fuel moto about this.

 

I agree, that cutting around a stock exhaust isn't going to guarantee decent results. I have a Supertrapp 2-into-1 on my bike and the muffler has around 2 1/2" diameter inlet, certainly much larger than a stock muffler.