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Discussion Starter #1 (Edited)
I figured it would be good to get an exhaust thread specific to the 765 platform started.

Arrow slip-ons are already available from Triumph and I see that SC Project already has their S1 system up for sale (looks amazing!).

I happened to have a Coffman slip-on sitting in the cabinet from my previous Street Triple 675 so I figured I would see if it fits, and it does without any troubles. Since the exhaust on the 765 routes under the left side of the engine rather than the right on the 675, it doesn't come out as far as it did on the 675.

I don't think it looks terrible but I'm not crazy about it by any means. It doesn't really look like a part of the bike...just hanging out there. This muffler doesn't do a whole lot in the muffling department, it is rather loud and I didn't keep it on my 675 for that reason. But, never the less, it was just sitting there so I figured I might as well do the experiment.

It's definitely WAY louder than stock, but I haven't ridden with it yet; was raining when I installed it. It has a mean growl to it, certainly sounds cool, but I have a feeling it's going to be louder than I want to live with. I have a lot of highway miles to get to work and the drone gets annoying after a while.

Here's a comparison of the sound, stock vs Coffman w/ baffle vs w/out baffle.

And some photos.






The heat shield does fit just fine with the Coffman muffler, I just didn't have it reinstalled when taking this photo.



The stock muffler is huge. Obvious weight savings...



Anyway, we'll see how long it lasts, but I'll ride with it installed for a while and let you know my impressions.
 

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Discussion Starter #3
That Coffman's exhaust look hideous....it also highlights how ugly the oil pan area is on this bike, and that's going to be tough for exhaust manufacturers to cover up/integrate with.


I think SC-Project did a great job dealing with the space. Looks better than the new Arrow imo.

I don't see the Coffman staying on my bike for long. Like I said, was just sitting there and I was bored. Gonna give it a run.

http://www.sc-project.com/triumph_street_triple_765_photogallery_S1_racing.htm

 

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The SC Project looks nice. I've only seen the SC Project and arrow on youtube so far.

Below is the clip of SC Project via YouTube:

 

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Discussion Starter #6
Just wanted to update everyone on what I found with this Coffman slip-on.

After riding the bike to work and back with some playing around, I felt there was a noticeable loss of power. As soon as I got home I swapped the Coffman back for the stock muffler and immediately noticed a difference. It felt much more playful, responsive and had more of the snap that I had become accustomed to over the last 1,000+ miles.

*Disclaimers*
To be fair, I did no tuning. However, an acquaintance of mine that also bought a 765 RS had an Arrow slip-on installed and reported that the dealer told him a remap was not necessary. Because of that I thought I should be good to go, that doesn't seem to be the case.
ALSO in Coffman's defense, they do not call this muffler out to fit the 765 models. It is technically for the 675.

The results from my unscientific butt-dyno:
1st gear power wheelies were still easy to accomplish with the Coffman but I felt like I needed to hold onto the revs longer for the same effect as the stock muffler.
2nd gear power wheelies went from plenty doable to difficult. With the stock exhaust it seemed like if I was around 8-10k all I had to do was close the throttle and then give it a good whack, maybe a small tug depending on road incline, and it would loft. With the Coffman was installed it had to be 10k or higher and I had to really give it the berries with a good tug on the bars. Even with that results were sometimes disappointing.
6th gear, 70mph roll on seemed lethargic with the Coffman in comparison to the stock muffler. Granted, the bike doesn't rocket forward in 6th @ 70mph, but it definitely didn't accelerate with the same amount of steam, albeit not a ton to start with.

Sorry, I have no video of all this and I realize it's not exactly scientific, but that's what I experienced. I ride like a hooligan and know where the bike sits with wheelie-able power and the Coffman definitely resulted in a loss of that power. General riding around didn't really yield much of a negative experience, the sound wasn't annoying like it was on my 675 and it had a really nice bark when it gets opened up. However, aftermarket exhaust typically makes the bike *feel* faster even if it really isn't, I felt the opposite.

No amount of good noise is worth loosing power. The stock exhaust doesn't sound bad either, and it looks much better between the two in my opinion. Perhaps once some sort of power commander becomes available or there's a tune the dealer can download that'll change things. For now, or once someone comes out with pipe they can prove doesn't loose power, it'll be stock for me.

Maybe somebody with an Arrow or SC-Project S1 can chime in on this?
 

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That SC Project system looks like it will roast your right foot. The Coffman looks like nothing more than an exhaust pipe tip with a baffle. Would not call that a muffler. Just my take.
 

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To each his own,but I'm not a Coffman fan.
On 675.net someone had a Daytona on the dyno and it lost 10hp from stock with the Coffman installed.
Free flowing is not always better,as I understand some back pressure is necessary for mid range power.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

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One reason I cant give up my 2012 675R is that you cannot beat the look of dual under-seat Leo Vince pipes in titanium!
 

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One reason I cant give up my 2012 675R is that you cannot beat the look of dual under-seat Leo Vince pipes in titanium!
Actually...you can, IMO ;)

Yanno...with that engine going to Moto2, I imagine there will be quite a few options for exhausts coming along.
 

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So i called Yoshimura and preordered the exhaust. They said they will be shipping mid August. The first run will only have 30 units. Im number 23. Pics and video when i finally get it
 

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Ugly...SC project looks much better IMO.


EDIT: Sounds awesome though!
Comparing the two, I wonder why the SC project has the extra piping snaking out of the collector upstream of the can. I think it would be interesting to see dyno runs comparing the two. The extra pipe length and added weight might be necessary for optimum performance, but if the overall difference is negligible - as it likely will be - I guess the decision would be driven, as always, by which one the buyer thinks looks and sounds better.

Just sitting at home after a hard week's TDY and rambling.
 

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Discussion Starter #20
Comparing the two, I wonder why the SC project has the extra piping snaking out of the collector upstream of the can. I think it would be interesting to see dyno runs comparing the two. The extra pipe length and added weight might be necessary for optimum performance, but if the overall difference is negligible - as it likely will be - I guess the decision would be driven, as always, by which one the buyer thinks looks and sounds better.



Just sitting at home after a hard week's TDY and rambling.


Pipe length affects pressure and heat retained in the exhaust system so I would imagine they did it for a calculated reason.

Being made of titanium that amount of pipe will weigh next to nothing so I wouldn't even consider it.

I emailed SC about the S1 and they said it does eliminate the cat and will require a tune.
 
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