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Next mufflers....S&S MK 45's?

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Old Jan 26, 2018 | 10:53 AM
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Default Next mufflers....S&S MK 45's?

I've posted before on my various attempts to find the right slip on mufflers for my 17 RGS. I ran stock for 5000 miles and was very pleased with how they performed and even sounded after break in, yet they were still just a bit too mild. After my Stage 1 I went with the Rinehart Motopro 45's and found them to be a bit boomy with a drone at cruising not to mention I'm certain I lost a bit of the exceptional low end torque the stock mufflers provided. Since then I've been running 2018 CVO mufflers with stock baffles and have found them to be good performers with good low end torque, but even more quiet than stock muffs.
I'm all but set to order a set of Street Cannons in order to get a bit more sound plus no loss of low end torque, but since then the MK45's with db reducer baffle have caught my eye as decent sound with no torque loss. Can anyone confirm they are good performers in the low end torque category?
 
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Old Jan 26, 2018 | 11:35 AM
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Looks like Fuel Moto will be using these for their upcoming cam testing, I would assume they could shed some light on your question. In videos they sound very similar to the moto pros that you say you didn't like so not sure it would be a win for you.
 
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Old Jan 26, 2018 | 12:11 PM
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Yes, with reducers in they don’t hurt the low end torque much, if at all. I still prefer the sound of the street cannons however. You can’t go wrong with either
 
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Old Jan 26, 2018 | 12:15 PM
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I prefer the S&S sounds over the SE. lol Just like everyone says, sound is subjective.

But I dont run any baffles. I love the sound and its not too loud, if thats what you're after. Me I want more sound, especially at idle. Cant comment on any power/torque loss though. I think my bike runs strong with the stage 1 I have. When I do the cam upgrade, I'll do a proper tune and get some numbers.

Also, I know a few here who have had quality issues with the SE slip ons. mjwebb I think is one. Might want to get some insight from him/them before you purchase.
 

Last edited by teedoff65; Jan 26, 2018 at 12:18 PM.
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Old Jan 26, 2018 | 01:32 PM
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I've been running the MK45's for about 15,000 miles now on my '17...... like most things S&S, they fit well, work as advertised, and sound great..... low end grunt is solid..... DW
 
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Old Jan 26, 2018 | 02:18 PM
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I exchanged an email with FM and they stated that the MK45's with the db reducer performed well in the low end torque category and that the baffle design with the S&S and Rineharts were very different. I agree that the outstanding flow of the Rineharts louverd baffles hampers low end torque and probably increases flow at the top. That was my experience as well. What I won't sacrifice is the brisk low end torque in exchange for higher end...that's not what Harley's are about IMO.
I'm not as concerned about sound as it isn't my top priority. Frankly I think it's silly to give up torque for sound but that's just me. That's why I'm hyper focused this time to give up nothing and would like, God forbid, to actually gain down load. It's been said that the Street Cannons offer no torque loss so that is likely my next step, but I do really like the S&S mufflers as well and am considering them. As it is now the CVO cans are plenty torquey but sound terrible. So still looking...
 
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Old Jan 26, 2018 | 02:57 PM
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Originally Posted by GliderXXX
I exchanged an email with FM and they stated that the MK45's with the db reducer performed well in the low end torque category and that the baffle design with the S&S and Rineharts were very different. I agree that the outstanding flow of the Rineharts louverd baffles hampers low end torque and probably increases flow at the top. That was my experience as well. What I won't sacrifice is the brisk low end torque in exchange for higher end...that's not what Harley's are about IMO.
I'm not as concerned about sound as it isn't my top priority. Frankly I think it's silly to give up torque for sound but that's just me. That's why I'm hyper focused this time to give up nothing and would like, God forbid, to actually gain down load. It's been said that the Street Cannons offer no torque loss so that is likely my next step, but I do really like the S&S mufflers as well and am considering them. As it is now the CVO cans are plenty torquey but sound terrible. So still looking...
Oh I agree. I dont really want to throw something on my bike that's going to cost me torque or HP, but I'm not a numbers chaser. I could care less if my bike is putting out 125 hp/tq. I DO care about sound. lol

I think there are so many combinations of set ups in these bikes that everyone can eventually be happy.
 
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Old Jan 26, 2018 | 05:03 PM
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Here is what MK45's sound like on a Stock header vs the RCX Tormentor header

 
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Old Jan 26, 2018 | 06:22 PM
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I have checked with Fuel Moto and some others about the difference's of both the MK45's and the Grand Nationals. I am picking up a set of the Grand Nationals and leaving the DB killer baffles in. Love the low end twist.
 
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Old Jan 26, 2018 | 07:07 PM
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Originally Posted by Prot
Here is what MK45's sound like on a Stock header vs the RCX Tormentor header

https://youtu.be/TV54NByrIWk
Wonder what cam they're using here.
 
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