RC51 Forums banner

1 - 17 of 17 Posts

·
Premium Member
Joined
·
68 Posts
Discussion Starter #1
Does anyone have any experience of Two Brothers race cans?

Mine came with these on and I love them, the sound is immense and sets car alarms off and upsets old people etc etc. I even re-painted mine with matt black end cans and gold leafed the Two brothers logo so they look super cool.

however my left have pipe keeps popping off the end. Where the carbon is rivetted to the body with the surround ring it seems that when its hot and under load from the engine the pressure is too much and it just blows off so I have to limp home, game over! :(

I inspected the baffles and some of which had been removed so I bought a repair kit and packed the cans out again thinking back pressure was the cause, however after a two hour ride it went pop again! :(

Its getting beyond a joke now and I am having to repair them every time I take the bike out unless I ride like im on a moped which isnt really the idea on such a thoroughbred.

Does anyone have any ideas how I can fix them back on permanently?

Cheers,

Stu :confused:
 

·
Premium Member
Joined
·
6,480 Posts
Twins are hard on mufflers anyway due to the large exhaust pulses.
I have buddy who also had 2Bros mufflers and his did the same thing.
The end cap blew right off and a car ran over it.
He had to search the Internet to find a replacement muffler set as 2Bros no longer made his model mufflers anymore.

I have akrapovic carbon-fiber mufflers and haven't had any problems with the rivets or end caps.
Is there some weakness in the design or issue with the rivets that may be causing your 2Bros mufflers to fail repeatedly?
 

·
Registered
Joined
·
1,193 Posts
i had the same problem with my aluminium jardine. never came off but always loosened up. make sure the rivets you replace them with are steel instead of alum. that helped alot with mine
 

·
Premium Member
Joined
·
3,186 Posts
like subsailor said.....v twins are hard on mufflers, especially on carbon fiber. Most guys in the Aprilia twin world don't recommend carbon fiber cans unless made by a high quality manufacturer like Akrapovic. They just don't hold up. Not saying two brothers is a bad company but they don't have the research and development/ build quality of Akrapovic and similar maufacturers.
 

·
Premium Member
Joined
·
68 Posts
Discussion Starter #5
The weird thing is that I thought it was a design flaw in that the carbon had slots cut into it which lined up with the rivet holes, so on the third repair cycle I drilled four new holes to make sure the rivets were enclosed on the muffler casing.

However, when it popped off again it looked like these holes had turned into slots as well, I can only guess that the rivets got so hot that they melted the carbon fibre allowing it to slip off?

I shall look for some steel rivets and see how I get on, if they go again I think I'll have to sell them for something else. Shame really though, lovely cans!

Cheers,
 

·
Premium Member
Joined
·
6,480 Posts
Unfortunately the rivets used by Akrapovic and others are the 5/16" stainless rivet, and most manual rivet tools can't handle steel rivets in that diameter.
I searched all over and couldn't find a manual tool that can handle steel rivets that size.
I'm trying aluminum rivets on my rebuilt Akra mufflers as a test.
Hopefully they will hold up.
If anyone knows of a manual rivet tool that does handle 5/16" steel rivets, please let me know.
 

·
Premium Member
Joined
·
8,328 Posts
Look at Harbor Freight for a pneumatic rivet gun. Those are the schiznit.:D

2Mother cans do sound good but this is not the first I have heard of this using their products and not just RC51 units have had this issue...
 

·
Premium Member
Joined
·
4,616 Posts
I have the Akrapovic full titanium race system, which came with Carbon sleeves & stainless rivets with a stainless band around the carbon - holding the titanium end can tightly (Interference fit) in place.

Like others have said, 2 cyl bikes, especially large capacity are hard on silencers. I replaced the wadding on mine twice already in 4 years and also two of the carbon sleeves because they discoloured and began to break up as the wadding burnt away over time / mileage. Definitely use the right sized rivets - with stainless or titanium either side of the carbon fibre so it holds well. A good rivet gun should work fine, no need for anything super heavy duty - use both hands to squeeze the tool and it should be fine.

Last time, I changed the carbon sleeves for titanium when renewing the wadding packs inside. The exhaust system will get louder as the wadding inside deteriorates but the sleeves won't be affected.
TBH I couldn't care less if the bike gets very loud - I wear ear plugs and ride slowly & at low revs when in residential areas and noisy bikes are safer.

For an RC51 that's ridden as it should and used for significant annual mileage, Titanium sleeves are always better.
Carbon's just too much maintenance for no particular gain compared to Titanium for a road bike.

 

·
Premium Member
Joined
·
6,480 Posts
...Carbon's just too much maintenance for no particular gain compared to Titanium for a road bike.
I knew the problems with c-f mufflers, but c-f was the only choice when I bought the Akrapovic full system.
I have the stainless rivets Akrapovic supplies, but my rivet took simply isn't designed to handle those rivets.
This is what prompted my search for a heavier duty tool.
 

·
Premium Member
Joined
·
4,616 Posts
You can buy Titanium replacement sleeves for Akropovic exhausts, no problem. I ordered these, plus re-packing kit, etc. for mine from Harris Performance in UK. No need for anything expensive as far as rivet guns go... As long as the fitting on the end of a tool will accomodate the rivet pin and grip it inside, then it should work OK...Just squeeze like hell.
 

·
Premium Member
Joined
·
68 Posts
Discussion Starter #12
I've now got my eye on some replacement cans-titanium ones just for the piece of mind. Like you said for an RC51 that is ridden properly throughout the year I agree that carbon is not as practical in this application.
 

·
Premium Member
Joined
·
6,480 Posts
You can buy Titanium replacement sleeves for Akropovic exhausts, no problem. I ordered these, plus re-packing kit, etc. for mine from Harris Performance in UK. No need for anything expensive as far as rivet guns go... As long as the fitting on the end of a tool will accommodate the rivet pin and grip it inside, then it should work OK...Just squeeze like hell.
Unfortunately, the only rivet tool I can find in my area is the cheap chinese tool that only works with aluminum rivets.
The handles not only do not have the leverage, but the jaws aren't strong enough to grip the steel rivet stem enough to shear the stem off.
The tool breaks before the rivet does.
My search continues, but the cheap chinese made junk permeates/pollutes the tool world.
 

·
Premium Member
Joined
·
3,186 Posts
I've now got my eye on some replacement cans-titanium ones just for the piece of mind. Like you said for an RC51 that is ridden properly throughout the year I agree that carbon is not as practical in this application.
which cans are you looking at? have you seen the Ladybird's from Simon? Couple sets on ebay.
 

·
Premium Member
Joined
·
4,616 Posts
Unfortunately, the only rivet tool I can find in my area is the cheap chinese tool that only works with aluminum rivets.
The handles not only do not have the leverage, but the jaws aren't strong enough to grip the steel rivet stem enough to shear the stem off.
The tool breaks before the rivet does.
My search continues, but the cheap chinese made junk permeates/pollutes the tool world.
Sounds like you have access only to cheap & nasty tools locally. It may be worthwhile hunting out something online of quality that'll work properly & last a lifetime. I can't remember the brand I have (& won't be near mine a few days) but it wasn't expensive and did the job fine.
Cost me maybe $40 in Japan & it does rivet nuts too (Useful for other things). I did have to squeeze very hard, but it worked fine.

Useful tip: Be sure to use masking tape around the holes you're working on to avoid scratching as the rivet stems break off.

Alternatively find someone locally who can do it for you, of course.
 

·
Premium Member
Joined
·
2,697 Posts
Just something remember from the race car days. We used steel washers on the back side of the rivets in high stress areas. I haven't tryed and I don't know if it would help in this applicatoin, but I would think it would grip the C/F around the rivet hole and be less likely to pull through. What I recommend trying is super gluing washers on the inside of the C/F sleaves to hold them in place during assembly.
James
 
1 - 17 of 17 Posts
Top