Rush Slip-ons installed...ehh
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Joined: Jun 2013
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From: St Louis
Rush Slip-ons installed...ehh
Installed a set of Rush slip-ons on my FXDC.
They sound GREAT when idling, revving, and accelerating.
Cruising at a constant speed they give off a drone/thwump that gets kind of old.
Decelerating they pop and gurgle (I don't mind the gurgle).
Will these characteristics change over time without any other changes? If I open up the air cleaner, tune, and pretty much complete the Stage 1 will that cause it to change?
Appreciate the input.
They sound GREAT when idling, revving, and accelerating.
Cruising at a constant speed they give off a drone/thwump that gets kind of old.
Decelerating they pop and gurgle (I don't mind the gurgle).
Will these characteristics change over time without any other changes? If I open up the air cleaner, tune, and pretty much complete the Stage 1 will that cause it to change?
Appreciate the input.
Road Master
Joined: Oct 2011
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From: Right where I belong!
This topic has been covered many times on multiple threads, just use the search function and you will find all the info you would ever want and more. Basic answer, yes a tune will get rid of your popping, but your exhaust sound is what it is........
Go Cards!!!!!
Go Cards!!!!!
Seasoned HDF Member
Joined: Jul 2008
Posts: 9,278
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From: southeast PA
Rush makes different size baffles. You could get in touch with them and see what they would suggest. A lot of riders here use those and can give you some advice based on their experiences. I'm sure some of them will chime in on this.
Road Captain
Joined: Oct 2010
Posts: 724
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From: SC Lowcountry
The Rush slip ons are a very free flowing design. What size baffles are you running? If you are running anything larger than a 1.50", you could drop down a size. That might help, but then again it might not. You could add some XIEDs to richen your AF ratio, which could also help. I'm running Rush Slash Cuts with 1.75" baffles, Ness BS, and a Power Vision tuner. Bike runs fantastic with no popping.
When you open up the A/C and get a tune it will be different. Probably still have the steady drone, just at a different pitch.
You can quiet it down a bit, AND get some extra power with the Thunder Torque Inserts.
You can quiet it down a bit, AND get some extra power with the Thunder Torque Inserts.
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Joined: Mar 2013
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From: Sacramento
I run Rush slip-ons with 2" baffles. I LOVE the sound of them. I had lots of pop and gurgle when I switched. I added a SE A/C and Power Vision and have been able to tune out 99% of the popping. I considered going to the 1.75" baffles to gain a little more backpressure but was completely unwilling to give up any of the sound of the 2" baffles. Seriously perfect. Nice deep thumpy idle, real loud when you crack the throttle, settles down when cruising.
I do think that the cruising tone will change a little bit for the better with a few hundred miles as the packing heats up and settles in.
I do think that the cruising tone will change a little bit for the better with a few hundred miles as the packing heats up and settles in.
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From: St Louis
Thanks everyone for the tips and advice.
Perhaps I jumped the gun on the "ehh". I do really like the sound of them at idle, acceleration, and revving. And after riding yesterday, I was able to somewhat avoid the "thwumping" that occurs at certain rpms.
I'm running the 2" baffles.
The popping is quite excessive and looks to be fairly common among those who haven't adjusted the fuel/air ratio. Looks like that's my next step. It pops during shifting sometimes, and always during deceleration...and quite a bit I might add.
Go Cards!!
Perhaps I jumped the gun on the "ehh". I do really like the sound of them at idle, acceleration, and revving. And after riding yesterday, I was able to somewhat avoid the "thwumping" that occurs at certain rpms.
I'm running the 2" baffles.
The popping is quite excessive and looks to be fairly common among those who haven't adjusted the fuel/air ratio. Looks like that's my next step. It pops during shifting sometimes, and always during deceleration...and quite a bit I might add.
Go Cards!!
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Cruiser
Joined: Aug 2012
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From: Chicago
My Cobra slips had decel pop like crazy with no other mods. Was worse for the couple days I ran the Stage 1 AC, but after tuning it, it's buttery smooth. Still have the gurgling on decel, but 99% of the popping is gone.
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Road Captain
Joined: Oct 2010
Posts: 724
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From: SC Lowcountry
I had the same issue with my 2010 FXDC. I was already running XIEDs before I installed the Rush Slip ons, but after the muffler install I immediately had the decel pop you describe. Are you sure you don't have any kind of exhaust leak? You can roll the dice & try a pair of XIEDs, but they might not be able to correct the pop. Go ahead and plan on changing out your intake/air filter & decide on a tuner. I'm partial to the Power Vision, but there are other ones out there that can correct your issue.
Decel popping does Not damage your engine...it is simply unburnt fuel that is burning in the exhaust tract after exiting the engine.
Most bikes with open air and exhaust and a performance tune will have decel pop.
Decel popping occurs when one of two things are present.
1. The bike is so lean the exhaust is superheated and is burning the unburnt fuel that is in the pipes (there is always some unburnt fuel in the pipes no matter how lean). This is very rare, and does not sound like it is what you are experiencing.
2. The AFR IN THE pipes is just right to burn the unburnt fuel. This is quite a common occurrence when free flowing pipes are installed (whether or not a free flow A/C is installed). It can also occur if there is an exhaust leak that is introducing extra air into the exhaust tract.
Check for leaks...if there are none, then move on.
To get rid of decel popping a lot of people put MORE fuel than is needed into the engine/over-richening the AFR so that more unburnt fuel goes into exhaust, changing the AFR in the exhaust so that is no longer optimum for combustion in the pipes. This is just a waste of gas. And if using decel enleanment found on most tuners it is still really hard to get rid of the popping/burbling when the injectors kick back in at about 1750 rpm.
Another way to change the AFR IN THE Pipes is to install Thunder Torque Inserts.
Not only will you get a deeper tone, you will get a nice bump in low and mid range power. They also change the AFR in the pipes and can reduce or eliminate decel pop.
Most bikes with open air and exhaust and a performance tune will have decel pop.
Decel popping occurs when one of two things are present.
1. The bike is so lean the exhaust is superheated and is burning the unburnt fuel that is in the pipes (there is always some unburnt fuel in the pipes no matter how lean). This is very rare, and does not sound like it is what you are experiencing.
2. The AFR IN THE pipes is just right to burn the unburnt fuel. This is quite a common occurrence when free flowing pipes are installed (whether or not a free flow A/C is installed). It can also occur if there is an exhaust leak that is introducing extra air into the exhaust tract.
Check for leaks...if there are none, then move on.
To get rid of decel popping a lot of people put MORE fuel than is needed into the engine/over-richening the AFR so that more unburnt fuel goes into exhaust, changing the AFR in the exhaust so that is no longer optimum for combustion in the pipes. This is just a waste of gas. And if using decel enleanment found on most tuners it is still really hard to get rid of the popping/burbling when the injectors kick back in at about 1750 rpm.
Another way to change the AFR IN THE Pipes is to install Thunder Torque Inserts.
Not only will you get a deeper tone, you will get a nice bump in low and mid range power. They also change the AFR in the pipes and can reduce or eliminate decel pop.