What do you guys think about a Full Two Brothers Exhaust System? Performance, sound? Any comments?

I was talking with a mechanic at a Yamaha Shop, and he told me something, but I think he is full of shit. He said that with the 954's putting a full exhaust system is "Stupid." By putting on a full system, I would gain power at the top end of the RPM range, but lose quit a bit at the low end. He said this was because of the HTEV valve in the exhaust. "Don't Fuck with it" That's what he told me.

As you all know, the 954's have a bit of a dead spot before 3000 rpm's but after that you better hold on to your ass. By adding an exhaust, what will this do to the lower RPM range? It's not like I redline my bike evertime I ride, so losing power on the lower RPM range would suck.

Personally I think he's full of shit, I would think you would gain power through the whole RPM range.

Comments??

you would but there would be a lul.... If you tucked the flapper under the air intake ducts then the lul would be lessened but not removed. You would find it annoying normally through 25mph zones in turns. Other than that with a full system you get the complete package! Sound and performance.
If you are a perfectionist freak like me you would end up getting the system, then you'd end up getting a pc3 and a custom map to iron out any and all kinks in the response.
other than that if you want it get it. Tuck the flapper and learn it's new personality in response, adjust your style, and ride like the wind :sprint:

Thanks for the input. You always answer my questions in detail and I appreciate it.

Just an add on to the ? above. Would it be almost pointless to just do a Slip on, since the only gain would just be the sound. I'm not really interested in racing the bike on the track, and not too keen on getting a PC. I just like to keep the bike "reliable" and don't want to sacrifice all this loss in the lower to mid RPM. Thanks for the suggestions.

You are welcome 954rider01. My pleasure. :) (that's why I'm still here besides this being my home away from home...lol


hey Psquared, in that case get what you find to be the best look/sound/price.
One thing though... try and settle for one that just bolts up to the 3/4 pipe after the htev to avoid having to cut anything like some bolt-ons do...
I'd have to do a search to find out which ones those are but it's quiting time here at work and I have to gear up for the ride home.

My Erion bolt on definately made a difference over stock. Sound and power were improved drastically.

I have a Two Bros. hi-mount system and it runs (144+ HP) and sounds great in my opinion.

I have the 2 bros full exhaust with the carbon fiber canister and its awesome. sounds awesome and the powers awesome!

I have the two brothers Carbon fiber can -slip on.

I didn't notice anything but the sound. I love the sound though. I got it mostly for my girl so she doesn't burn herself on the can. A little noise also helps in traffic.
I also tucked the flapper- I think that did amke a difference, but it not like a whopping 10hp.

My Bike dynoed at 133HP with the slip on. I have no before dyno, but that is on par with stock output.

i think the best decision is to get a full moriwaki system... not much else to say on that one.