I got a 2008 rg with true Duel rineharts 3 1/2 inch older tin sound ok a friend bought A 09 rg with slip on 4 inch rineharts I got from him for cheap I know they are1 3/4 inlet and my head pipe is 2 inch outlet I can make it work..my question is dose anyone think 1/4 step down in pipe to muffler will cause a big power difference or not a noticeable difference..all that's done to bike it zipper ac true duels and race tuner thanks in advance and I know 90% of aftermarket duel exhaust uses 1 3/4 headers anyway

I edited this for the motorcycle challenged guy that Replied

 

Do what? Speak English and someone may answer you with an intellectual answer

 

If both pipes are the same size where it connects to the head and the slip ons fit on the other end snug, all the clamps line up, exhaust hangars line up, it fits good throughout the entire system, I dont see a problem 1/4 diff shouldnt make that much of a diff, if anything give it a tad bit of backpressure, I might be wrong, if I am someone will throw a wrench at me and let me know, lol..

 

The 09 frame is wider than your 08, so I would be surprised if that set of pipes will fit. We usually recommend pipes up to 08 for bikes up to 08 (I have 08 pipes on my '90). However if you have them you can offer them up to see if they will work.

 

As wide open as the Rinehart mufflers are, it could actually help by adding a bit of backpressure. But I'm concerned as to whether or not they will fit..

 

Many changes between these two bike years (2008 to 2009). Have you mocked-up the exhaust to see if it's close to fitting..??

I'd reconsider merging a 2" heater into a 1 3/4 pipe...are you planning to slot the header to go over the pipes? Not something I'd recommend...JMO...

 

I'm not using the header of of the o9 just the slip on's which are Reinhart so only thing I would be changing Is the mufflers

 

Your 3.5 rineharts should be 1 3/4 inlet as well. If your bike is running good with the current non-stock headers, changing mufflers only shouldn't be a big deal.

 

As I wish was the case no I have true duel Step headers
Start at 1 3/4 end at 2 inch I heard that this headers are good for big inch motor and hi rpms I only have ac headers and race tuner I have a 2 " to 1 3/4 reducer adapter to use the smaller inlet mufflers I don't think it would hurt my performance since 1 3/4 is what 90% of aftermarket headers are

 

I knew/know what you are saying but your spelling and punctuation and overall delivery is rediculously butchered. I speak "redneckanese" fluently and listen to/read horribly butchered English from an El Salvodorean and Mexican everyday at work...yet your writing was hard to understand. HAHA Look at the replies. Most people think you're talking about changing head pipes and all.

As for your question on the mufflers, if you have an adapter, try it and see. You'll feel it if it makes that much of a difference. I can't see where it would change it all that much. As another said, it may add a little back compression and give you a little more "pep"