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Just fitted the new Akrapovic can and with the little baffle thing removed the increase in the level of sound is very noticeable, sounds a bit fruitier too >:)
I did order the full Akrapovic system but the headers are not in yet, can anyone confirm for sure if the Akrapovic headers for the GS are identical? Also if the GS headers are the same, which GS model year? (I am guessing the twin cam GS just before the LC GS are the headers I need? I know the headers for the RT are different in the angle where the silencer attaches.

Mods so far... Rear sub-frame removed (huge saving in weight), Seat hump, Wunderlich tail tidy, Led indicators, Wnderlich nose fairing, Akrapovic can, Renthal bar (when I get round to fitting it).
Probable future mods... Suspension upgrade front & rear, paint job, move foot pegs. Probably more.
 

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No Akra headers as yet. Go Remus.

GS headers are different.
 

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ok :confused: Akra told me they wouldn't fit
as an Akra sales rep I would tell you the same ;)
If you check the part numbers (18117716484) i.e. on realoem.com you will see, that they are identical for nineT and GS(A) , 2010 and later
 

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I had Akra headers on my GS. The Remus setup is far neater than the Akra headers. Also the Remus removes the balancing pipe.
 

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I had Akra headers on my GS. The Remus setup is far neater than the Akra headers. Also the Remus removes the balancing pipe.


I agree the Remus headers are nice, I hope they fit the Akro link pipes as I already have the high and low set up link pipes and Akro end can, I'll try and find out if the are the same diameters.
 

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I agree the Remus headers are nice, I hope they fit the Akro link pipes as I already have the high and low set up link pipes and Akro end can, I'll try and find out if the are the same diameters.
From what I've read, remus headers fit both the stock akro and the titanium akro silencers.
 

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I'm wondering what the UK MOT regulations would say about a Catalytic Converter deletion on a motorbike.... From my time on car forums it seems like an obvious Cat deletion is a MOT failure. Companies offering Cat removal cut the Cat casing open, remove the internals then put it back together again, so it's not obvious that the Cat is no longer there. That gets by the issue unless the MOT tester notices any obvious tampering...
 

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I'm wondering what the UK MOT regulations would say about a Catalytic Converter deletion on a motorbike.... From my time on car forums it seems like an obvious Cat deletion is a MOT failure. Companies offering Cat removal cut the Cat casing open, remove the internals then put it back together again, so it's not obvious that the Cat is no longer there. That gets by the issue unless the MOT tester notices any obvious tampering...
From what I read, it is not an issue in Oz with bikes built before 2016. The fine for running catless cars is huge!
 

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I'm wondering what the UK MOT regulations would say about a Catalytic Converter deletion on a motorbike.... From my time on car forums it seems like an obvious Cat deletion is a MOT failure. Companies offering Cat removal cut the Cat casing open, remove the internals then put it back together again, so it's not obvious that the Cat is no longer there. That gets by the issue unless the MOT tester notices any obvious tampering...
Dave


I've never had a problem at MOT time with bikes with full systems in Scotland,
 

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I've just done a quick google search and it seems that at present there is no UK emissions test for motorcycles, and no direct mention of MOT issues involving bikes having Cats removed....

Sounds positive!
 

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It is always good to go with a header/exhaust combination from the same manufacturer and not mix/match.Also balancing headers with balancing pipes tend to give you more torque from idle to 6000rpm while headers without balancing pipes on BMW boxers are weaker down low and in midrange but give you a little bit more on top...But mostly it is only sound.
 

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It is always good to go with a header/exhaust combination from the same manufacturer and not mix/match.Also balancing headers with balancing pipes tend to give you more torque from idle to 6000rpm while headers without balancing pipes on BMW boxers are weaker down low and in midrange but give you a little bit more on top...But mostly it is only sound.
Wrong, wrong and err.... wrong

Balancing pipe is for 1) equalising pressure 2) emissions 3)allows exhaust gas scavenging between cylinders 4) strength. No performance benefit proven
 

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Roadrunner all theory is grey.Had a R1200S with both Akra and Remus headers on the dyno.The one with the interference pipe made more power and torque where it counts in low and midrange.The one without the interference pipe lost power and torque below 6000rpm and made like 2 hp more on top which I did not feel...
A new R1200GS-LC made even less power than the stocker with an aftermarket header in a recent test in Cycle World or Motorcyclist.It's mostly sound due to the missing cat!Louder sounds faster...;-)))
Tell some Ford or Chevy V-8 tuners that balancing pipes or X-pipes don't give no performance benefits.Have you ever looked at the header pipe of a BMW S1000RR?Maybe not top end hp with is theoretical anyways but for sure more torque!
 

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Balancing pipe is for 1) equalising pressure 2) emissions 3)allows exhaust gas scavenging between cylinders 4) strength. No performance benefit proven
Nope.

There is a reason high end headers (talking about bikes here) all include cross pipes. In cars an H or X pipe is normally used. Below is an cut and paste I found.

H-pipes were first installed to quiet this exhaust noise. When the two close firing cylinders are exhausting on one bank, there is nothing happening in the other bank, so connecting both pipes effectively enlarged the exhaust system, allowing these exhaust pulses to exit through both sides of the system. It was found that, with the addition of an H-pipe, exhaust noise could be reduced by as much as 2 decibels. Adding an H-pipe also increases power. Even when headers are installed, these close firing cylinders are competing for space in the exhaust pipe after the collector, which creates backpressure and reduces power. Connecting the exhaust pipes allows pressure to escape to the other side of the system, with a resulting gain in low-end and mid-range torque.

Removing the cross pipe wll decrease low RPM power. Other mods done at the same time could easily recover this loss and add more power...

RobertVP
 

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Even when headers are installed, these close firing cylinders are competing for space in the exhaust pipe after the collector, which creates backpressure and reduces power. Connecting the exhaust pipes allows pressure to escape to the other side of the system, with a resulting gain in low-end and mid-range torque.
I've looked at the remus extractors (no cross pipe) and compared to the stock ones. There is no way that there would be more back pressure in the remus extractors. They go two into a larger diameter junction and a cross piece would not change that equation. there is no "other side of the system" as they both meet (in stock) prior to the cat, where most of the pressure builds up. Or in the case of a full system, does not build up, as there is no cat.

Noise advantage and emissions advantage? possibly.
 
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