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Very Dissatisfied With My Two Brothers Carbon Fiber Exhaust Pipe

21K views 41 replies 24 participants last post by  Vwvanagon 
#1 · (Edited)
I changed the exhaust pipe recently on my Honda CBR250R with a Two Brothers carbon Fiber Black Series slip-on pipe. It cost nearly US$500.

Meanwhile, I had heard of other people complaining of Two Brothers Carbon Fiber pipes starting to turn yellow/brown after a while, but I didn't think much of it at the time.

After driving only about 1,200 kilometers on the bike with the new Two Brothers pipe installed, the carbon fiber started turning brown at the end where it connects to stainless steel section of the pipe as seen in the attached photos. In fact, the stainless steel section of the Two Brothers assembly also turned from silver to completely gold as you can see here too.

Before buying the pipe I had also read on the Two Brothers web site that after a period of use the pipe might need to be repacked to avoid the browning. Honestly, I have never seen this problem even occur with other brands like Yoshimura and others to begin with.

Anyway, I didn't expect my pipe to start having problems after such a short period of time or need to be repacked right away so I wrote to Two Brothers when the pipe started turning brown suggesting that the pipe might be defective.

Their response was:

"We do recomend customers to repack the muffler. Change in color of the muffler is a clear sign that the muffler must be repacked. Muffler durability is linked to driver's riding style and varies depending on many factors."

So I reiterated that I had only driven about 600 miles with the pipe installed before this started happening and again I thought it was defective. Their response again was:

"No defect. The packing material will be used as you use the muffler and it is pert of the maintenance to repack it as need it."

This tells me their pipes are very poor quality to begin with since I do not drive my bike hard or ride it in any way that is not recommended. And the fact that they are not willing to resume any responsibility at all after I paid a lot of money for the part, means their customer service is quite bad too.

At this point I am not going to bother to spend more money to repack it. It is already ruined anyway. The attached photos were taken about 2 months ago and the pipe has even more discoloration now. I will just leave it as is and eventually replace it with another brand and be finished with it.

Lesson learned not to buy Two Brothers ever again, full stop.
 

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#6 · (Edited)
I've had my 2Bros exhaust for close to 4000k's and have had no problem with the carbon fiber changing color, although I do use Inox lubricant on it every time I wash the bike.(cheers to Aufitt for that tip)
Looks like yours wasn't packed properly in the first place, not enough packing down the burn end causing a hotspot.
I have also heard(though not sure if true)that a carbon s/o will overheat and burn if you run the engine for long period without the airflow to cool the can eg. dyno tuning.

To repack you drill out the pop rivets to remove end caps, repack and replace rivets.
 

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#8 ·
My stainless pipe has turned a beautiful gold/purple colour.. means you are using it properly.

As for the tarnished printed carbon, yes repack it as its getting hotspots and that's where cheap companies like 2 brothers scrimp on packing.
I'm going to repack my Akra anyway.. its easy as long as you can drill stainless rivets.

A good check is to rev your bike and see where the outer shell 'pulses/flexes' with the beat of the engine.. it often shows a hollow spot meaning the packing is loose or non existent.
Dirtbike riders repack annually.
 
#12 ·
the carbo can looks like exhaust might be escaping out the end cap fitment and discoloring. I have never seen discolored carbon fiber, but I have never seen that pattern either.

yoshi has repacking videos on their site. yoshi's need repacking too.
I really liked the stainless full systems that turn gold, they look like titanium after being heated.
 
#32 ·
yoshi has repacking videos on their site. yoshi's need repacking too.
My mate has a gsxr1000 with a full Yoshi carbon fibre exhaust. Spoke to Suzuki / Yoshi who said it doesn't need repacking unless you're racing. For street use no need to repack.

I thought that was a bit strange. I've done about 8000km on my Musarri slip-on and still sounds same as day one. Haven't considered repacking it at all.
 
#13 · (Edited)
Akrapovic makes nice carbon fiber pipes. The one for the CBR250R looks really nice. You can have a gander on YouTube if you want:



Meanwhile there is a good chance I will just live with it. As long as the pipe keeps on working there is probably no point in throwing any more money at this bike for now. If it were a bigger, more expensive bike I might consider another pipe change, but I don't have enough invested in the bike to keep throwing $500 pipes at it.

Sadly though, seeing how awful the Two Brothers customer service is, and with them probably having so many regular complaints like mine with the QC on their pipes being so low, it seems like a dead end with them to try and get any warranty coverage whatsoever even though the pipe was probably not packed correctly from the factory. And, regardless of how I ride, this shouldn't happen so quickly on a pipe after only 1,200 km despite what their customer service staffer said. The fact that it did happen so soon after installing the pipe either means it is defective, has junk build quality, or both and has nothing to do with how I ride the bike.

As an aside, when I was over at the mechanics shop having the pipe installed a couple of months ago there was a guy there with a CBR 1,000 and he had a Two Brothers carbon fiber pipe on his bike already. He saw my pipe being put on my bike and he said he likes the sound of the pipe on his bike, but that his turned yellow and brown and he showed me his so that I was aware of the problem with Two Brothers pipes. I figured at the time he was either riding too hard or the pipe was just old and starting to wear out. Now I know it was probably neither of those issues. Just a bad quality pipe brand to begin with if it happens so easily and quickly on a bike like mine which is only a 1 cylinder engine.

I also did a quick Google search on "Two Brothers Exhaust Turning Brown" and I was surprised how many threads came up on other forums about it being a problem. One guy even wrote on the Motorcycle Superstore site how on his GSXR it started happening the first day he put the pipe on the bike!

I wish I had known about this problem before and I would have for sure bought another brand instead. And it's an even bigger slap in the face when the manufacturer tries to blame it on you for not repacking the pipe when the pipe was still practically brand new as the problem started developing. Seeing how Two Brothers tried to blame the problem on me to avoid having to take responsibility at all for giving warranty coverage just adds salt to the wound.

If I ever modify another bike though Two Brothers will never make the short list again. And frankly speaking, a garbage quality pipe and a garbage company from my experience whilst the pictures speak for themselves.
 
#16 ·
Sorry that a change in color is bothering you so much but I wouldn't say it is because of bad quality or faulty packing. Exhausts are hot and change color. The Carbon that TwoBros is using is very light and has minimal paint or varnish on it because that doesn't make it work any better. Next time you see some bikes with different exhausts, take a look to see how many of those cans still look like new.
 
#17 · (Edited)
Thanks Sendler. I have actually seen a lot of other Carbon pipes. Yoshi, etc and I can't say I have seen any others that have the problem mine does.

I didn't want to burst killstrelok's bubble about his pipe and the photo he put up saying that his has 4,000 KM on it and no discoloration, but actually when I look at his picture it does look like it is yellowing to me a bit.

But with his pipe the yellowing is more uniform throughout the pipe. With mine it is also starting to happen to the rest of the pipe now in the same way his has yellowed a bit, but what bother's me are those heavy blotches of discoloration at the end of the pipe on mine. That I would say is not normal. In fact, I have seen carbon fiber pipes on big 1,000cc Yamaha R1 and Ducati sport bikes and the like where the pipes are under the back seat where they are easily visible and I didn't see those pipes changing color at all. And those bikes probably get a lot hotter. The whole beauty of carbon fiber is that it is supposed to be able to displace heat so well and as a result not discolor.
 
#20 · (Edited)
You are correct marcbkk, my pipe doesnt look like it did new, but as you said is a more uniform discoloration caused by UV exposure as much as heat I expect(this is no surprise though) . Your pipe should have been replaced by 2Bros as it is obviously a manufacture defect.
As already posted, once the color becomes annoying to me it will be out with the heat proof paint and spray it black.
I also will not buy 2Bros again, as there are better options available now.
 
#21 ·
No way should that muffler should need re packing already. I would be pissed off to. Never been a big fan of two brothers exhaust and after reading this I am even less impressed. Friend bought one and was so unhappy with it he took it back off and ordered a Leo.
 
#22 · (Edited)
I ordered mine a month before this thread started and crossed my fingers that this would not happen to me. Well it did, I noticed some bubbling and discolouration on the top.
I have put about 5000km on this exhaust which is about the same as the manufacturers re-packing interval of 3000 miles. I have read that they do not offer a warranty on their carbon fiber mufflers. So I thought I would have to live with the problem.

As riding season is nearing for us northern folk, I thought it would be a good idea to re-pack the muffler.

So I get the cap off and pull out the fiberglass blanket and noticed the whole top part of the blanket near the pipe end was burnt right thru. No wonder the exhaust started to bubble. I also noticed that is was a poor packing job as the seam of the blanket was on the top part of the muffler and was the thinnest part of the packing.
I am going to repack with FMF loose fill as I don't believe the blankets do a good job due to being thin at the seam.
 

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#23 ·
doesnt look that bad mate, the design sort of masks it..
youre aware of it so tho its real you notice it more..

my lv evoII [second owner, original packing still] has no
discolouration in black/matt black-grey carbon, mid pipe
has also slightly burnished which is normal for good
stainless steel.. she took a low speed side impact
from a car recently, left cars paint on end cap and
carbon of cannister, caused rear of bike to 'jump'
half a meter away..
no damage to carbon cannister..
[to my pleasant surprise]

i did fit it carefully etc, but that was easy as its
obviously well designed and made for this bike
and its lines and fittings etc..
still, quite pleased it took that impact so well..

for what it worth this member can recommend
lv evoII carbon s/o as excellent for the $..
[also obviously excellent akro for higher $]
 
#24 ·
it's not as bad as some of the others I've seen, it hasn't really browned. However the resin does seem to be a little more brittle in those areas. I don't want to push on the bubbles to hard.

It's just disappointing that they make such a nice looking exhaust (even using magnesium in the cap) and then they cheap out on the packing (which is probably a $10.00 or less cost for them). I paid $12.00 CAD for the FMF stuff.
 
#31 ·
it's not as bad as some of the others I've seen, it hasn't really browned. However the resin does seem to be a little more brittle in those areas. I don't want to push on the bubbles to hard.

It's just disappointing that they make such a nice looking exhaust (even using magnesium in the cap) and then they cheap out on the packing (which is probably a $10.00 or less cost for them). I paid $12.00 CAD for the FMF stuff.
Did you blank off the air injection system? I would strongly recommend this to avoid high exhaust temperatures.

Regards Roadster
 
#26 · (Edited)
In my mind, any exhaust that needs repacking ever is not fit for purpose.
I don't know if I can agree with that statement. Although the CBR250r is not a performance motorcycle, some of us tend to add performance parts. While I can agree that non performance mufflers ( like the stock muffler )should not need to be re-packed. Performance mufflers that use fiberglass packing will need to be repacked. as fibers get blown out or become wet, the performance dwindles and the carbon fiber resin can be damaged as the heat increases and the insulation thins. I am commenting on my experience with the inferior manufacturer packing job done on an otherwise performance muffler.
 
#28 ·
Any carbon fiber slip on really needs to be monitored for the slightest sign of discoloration (browning) to the carbon fiber weave. On the FMF Apex Carbon Fiber slip on, FMF uses a small re-pack indicator that is attached to the body, which will indicate the need for repacking before any heat damage occurs.

It does seem unusual that the Two Brother Carbon Fiber slip on's have such a short mileage interval between repacking. My FMF has well over 8000 miles (13,000 km) since I first installed it on the bike, and still shows no sign of needing to be repacked yet.
 
#36 ·
the whole exercise of muffler repacking is mostly unheard of in the automotive performance world.
I think we are confusing automotive flow thru mufflers and glasspack mufflers.

Flow thru's are those rectangular boxy mufflers that have no packing in them. they muffle sound by using multiple chambers for the soundwaves to bounce off of. High performance flowthrus are usally stainless steel and will last a very long time.

You can buy glasspacks for automobiles too. these look like motorcycle exhausts. brand names such as supertrapp, thrush, cherrybomb. the supertraps are repackable and because of that are meant to last a very long time.
The cheaper cherrybombs and thrush's are not repackable and are meant to be disposable.
 
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#33 ·
I remember buying a Yoshi for my FZ8 and it did recommend on their site to repack once a year (but sold the bike after a year). I have termignonis on my 2013 MOnster 1100 evo, and the carbon fiber looks just like after day 1 with now 6500km on it. Pipe changing color like that after only 1200km on a 250cc bike, to me only means (1) poor design or (2) poor quality. I've had TB pipes before and other then being too loud, quality seemed good.
 
#37 ·
I am so happy with my box stock CBR250 and really get a good laugh at those who waste their money on nonsense after market crap. The sellers of this junk are also laughing all the way to the bank. They got you, fool. You should feel disappointed, bad, stupid etc. a big waste of money and time.
It's only a 250 cc single, get real. RIDE it for what it is.
 
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