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So Fuby....I have watched your videos on the Coffman exhaust.. Now, that you have had some time with it, are you still liking it?

I am NOT looking for the loudest. In fact something marginally above the OEM would be fine for me. But, that $230 price and look of the pipe is sure attention getting.

Curious to know how you feel about it now.
 
So Fuby....I have watched your videos on the Coffman exhaust.. Now, that you have had some time with it, are you still liking it?
Welp... My Ninja is under covers till the spring time now.. But I love the Coffman..it sounds to "me", what this Bike should sound like coming from the dealer.. it is loud enough to hide the lawnmower sounds from the front of the engine and still quiet enough not to offend my ears.. I been around a few Harley's in my days.. this doesn't even rate to that noise level.. I been waiting to see how L337 liked the add on header he purchased and it seems that failed to make a difference in performance.. so I will be content with just this slip on .. it seems to be well made and should last a long time.. I always use the baffle.:grin::nerd::grin:
 
I been waiting to see how L337 liked the add on header he purchased and it seems that failed to make a difference in performance.. so I will be content with just this slip on .. it seems to be well made and should last a long time.. I always use the baffle.:grin::nerd::grin:
I love the way the Coffman sounds as well. Baffle in makes more power. Adding the musarri header made the exhaust take on a slightly deeper note.
 
I love the way the Coffman sounds as well. Baffle in makes more power. Adding the musarri header made the exhaust take on a slightly deeper note.

I see what ya did there... now I am going to have to hear the comparison Videos.. sigh, you just want me to spend more money.. sigh... lol.. thanks for the headsup.

:grin::nerd::grin:
 
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I see what ya did there... now I am going to have to hear the comparison Videos.. sigh, you just want me to spend more money.. sigh... lol.. thanks for the headsup.

:grin::nerd::grin:
I'll make another exhaust video in the same spot I made my last one for comparison. The note isn't significantly different, just throatier with the header.
 
L337sponge... I went to see an updated video on youtube.. umm. I seen a guy canyon riding on a Honda Magna.. imagine that..:) I been content with just the slipon btw...
 
L337sponge... I went to see an updated video on youtube.. umm. I seen a guy canyon riding on a Honda Magna.. imagine that..:) I been content with just the slipon btw...
I totally forgot to make a follow on video. I need to design a laguna baffle to make my bike pass tech at some local tracks. I'll probably wait to make another video until I get that figured out... Honda Magna is a great daily. I'll be posting some racing footage at the end of the month.
 
Those who have run this slip on without a PCV, do you feel the bike runs too lean? I consistently get pops from the pipe when letting off the gas in low rpms.
Yep, mine was running lean and popping. When we did a base run on the dyno (before changing anything) the air-to-fuel ratio data showed it was running super lean. So bad that the dyno tuner guy commented on it.
All sorted now though.

Edit: Sorry I just realised you were probably wanting Coffman specific info?
But if its popping, it's running lean.
 
Yep, mine was running lean and popping. When we did a base run on the dyno (before changing anything) the air-to-fuel ratio data showed it was running super lean. So bad that the dyno tuner guy commented on it.
All sorted now though.

Edit: Sorry I just realised you were probably wanting Coffman specific info?
But if its popping, it's running lean.
Haha I was looking for Coffman specific info. I’m pretty sure I’m going to need a PC. Would a block off plate to the AIS help with the leaning of the bike due to the slip on?
 
Haha I was looking for Coffman specific info. I’m pretty sure I’m going to need a PC. Would a block off plate to the AIS help with the leaning of the bike due to the slip on?
They do say it reduces popping doing this mod but the PAIR valve injects air into the exhaust port which is on the other side of the combustion chamber so I cant see how it could lessen the lean mixture. However the O2 sensor is down stream of the exhaust port which is connected to the ECU so maybe... Someone more learned than myself may be able to shed more light but either way it's a bit like a bandaid fix. Ideally your still going to need to either fit a PC or get your ECU flashed to get your fuel maps matching the characteristics of your new pipe.
Or, just live with the popping and the compromised performance and save your $$.
 
They do say it reduces popping doing this mod but the PAIR valve injects air into the exhaust port which is on the other side of the combustion chamber so I cant see how it could lessen the lean mixture. However the O2 sensor is down stream of the exhaust port which is connected to the ECU so maybe... Someone more learned than myself may be able to shed more light but either way it's a bit like a bandaid fix. Ideally your still going to need to either fit a PC or get your ECU flashed to get your fuel maps matching the characteristics of your new pipe.
Or, just live with the popping and the compromised performance and save your $$.
I haven’t noticed a decrease in performance, I’m more worried about damaging the engine by running it lean. At the same time I also don’t want to drop 300 dollars on a power commander just to run a slip on. I’d rather just spend half and get a booster plug in that case.
 
I haven’t noticed a decrease in performance, I’m more worried about damaging the engine by running it lean. At the same time I also don’t want to drop 300 dollars on a power commander just to run a slip on. I’d rather just spend half and get a booster plug in that case.
Cool. What I meant by compromised performance was that you wont release the full potential of the Coffman unless you tweak the fuel maps to match it.
 
I put one of these on my 2019 krt and drove for about 60 miles and I am removing it now.
The pictures and videos of this muffler are a little bit deceiving, the muffler is smaller in person and while it has a great sound at idle it is entirely too loud.
At 5 or 6k rpm it is almost to the point of hurting your ears much worse at 11 or 12k.
Maybe some people will like it but just too much for me.

I am now at a custom motorcycle shop that is building a custom muffler for me now, for less than what I paid for this one.
 
I put one of these on my 2019 krt and drove for about 60 miles and I am removing it now.
The pictures and videos of this muffler are a little bit deceiving, the muffler is smaller in person and while it has a great sound at idle it is entirely too loud.
At 5 or 6k rpm it is almost to the point of hurting your ears much worse at 11 or 12k.
Maybe some people will like it but just too much for me.

I am now at a custom motorcycle shop that is building a custom muffler for me now, for less than what I paid for this one.
That's exactly how I felt when i first got it and I can confirm most exhausts sound that loud, but I am used to it now and I love it. My friend has a 2bros slip on and it's louder and I've also heard the mussari which is loud too

I'm sure there's is silent ones out there but I love the coffmans now
 
while it has a great sound at idle it is entirely too loud.

I'm sure there's is silent ones out there but I love the coffmans now
I "never" got that.. never once thought, wow this is to loud...:)
Yeah... I am pretty sure most buy slip-ons for a sound boost... I enjoy the Coffman...nothing near a Harley etc..
I like your bracket too btw.. nice..



I am looking forward to the custom one "Silent" comes up with though... that's kinda neat too do... :clap:
 
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I "never" got that.. never once thought, wow this is to loud...:)
Yeah... I am pretty sure most buy slip-ons for a sound boost... I enjoy the Coffman...nothing near a Harley etc..
I like your bracket too btw.. nice..



I am looking forward to the custom one "Silent" comes up with though... that's kinda neat too do... :clap:
Aliexpress Bracket :)
 

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