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Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Mon Jul 05, 2021 5:02 pm
by Casbar
For some reason I thought the 2019 wasn't EU5 and the 21 was, but I could be wrong there. Shouldn't be putting an EU3 can on a EU4 or 5 bike. But you shouldn't ever speed either  8)

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Mon Jul 05, 2021 5:22 pm
by David.
This is what MCN have to say on the matter, https://www.motorcyclenews.com/advice/m ... -silencer/

"In relation to modified exhausts it’s illegal to modify the system to make a vehicle noisier after it has been ‘type approved’."

Euro 5 is "type approved".

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Mon Jul 05, 2021 5:26 pm
by hammo
I had the engine management (triangular orange ) light come on my 2019 1250RT following the information booklet i booked it in Coopers Sunderland to be inspected , the mechanic forwarded a video explaining that the flap had stuck and the servo unit failed all repaired under warranty .

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Mon Jul 05, 2021 6:06 pm
by David.
RTs4me wrote:The Akra was the one I had on my previous 1200LC, with a single tailpipe outlet. It fitted the 1250 perfectly well, but the 1250 Akra has twin outlets.
The 1200 Akra is only Euro 4 approved, that'll be why Akra have developed the Euro 5 version for the 1250.

At around £1,000, it's understandable why folks would use a 1200 silencer on a 1250.

When the exhaust flap packs up, will BMW turn around and say, "sorry mate, you had the wrong silencer fitted".

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Mon Jul 05, 2021 6:25 pm
by Casbar
David. wrote: The 1200 Akra is only Euro 4 approved, that'll be why Akra have developed the Euro 5 version for the 1250.

At around £1,000, it's understandable why folks would use a 1200 silencer on a 1250.

When the exhaust flap packs up, will BMW turn around and say, "sorry mate, you had the wrong silencer fitted".

Could do, but if I had the warning light and checked that my flap was stuck, I'd put my standard can back on before taking it to the dealer, 10 min job. But as it is a known fault, think they would struggle with that one, especially as my Akra was purchased from them.

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Mon Jul 05, 2021 7:47 pm
by Levisp
David. wrote: When the exhaust flap packs up, will BMW turn around and say, "sorry mate, you had the wrong silencer fitted".

If they did then they would seriously need shooting. The exhaust valve failure has nothing to do with the silencer fitted. Thats actually funny. Sorry sir can't fix your exhaust valve, I see you have different tyres fitted from OEM. This must be a wind up, right.

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 8:16 am
by David.
Exhaust systems are designed to deal with the volume of waste gases produced by the products of combustion from the engine. The 1250 (1254cc) engine capacity is 84cc greater than that of the 1200 (1170cc). When fitting an Akra (performance) silencer, surely it would be best to fit the correct one for the bike.

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 9:07 am
by Casbar
David. wrote: Exhaust systems are designed to deal with the volume of waste gases produced by the products of combustion from the engine. The 1250 (1254cc) engine capacity is 84cc greater than that of the 1200 (1170cc). When fitting an Akra (performance) silencer, surely it would be best to fit the correct one for the bike.

Yes it would, but if you have already spent £800 on one Akra the prospect of selling it for a vastly reduced cost and then spending another £800 for little or no reason doesn't sound attractive. I actually asked Mr BMW if fitting my EU3 Akra to my 2019 1250 would have and impact at all, the answer was Non! I even asked Akra and they said no impact apart from one has a single baffle and the other now has two, but it won't blow anything up or harm anything engine wise. Now if someone would like to buy my EU3 Akra off me, I will consider buying a new one :)

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 9:10 am
by Levisp
David. wrote: Exhaust systems are designed to deal with the volume of waste gases produced by the products of combustion from the engine. The 1250 (1254cc) engine capacity is 84cc greater than that of the 1200 (1170cc). When fitting an Akra (performance) silencer, surely it would be best to fit the correct one for the bike.

Understand that but I bet if you took the two apart there would be little difference between them. I'm sure there is more between stock and Akra and that's OK. Me I'll stick to my nice chrome stock can.



Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 9:12 am
by Levisp
Blimey £800 on an Akra !! They are having a laugh.

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 9:41 am
by David.
More info. here on the Euro 5 noise regulations, https://motorbikewriter.com/bmw-1250-boxer-quieter/

"BMW is expected to drop the noise levels from 92dB for the 1200s to 88dB for the 1250s."

Hence why Akra have had to produce a new silencer for the 1250, which is quieter than that for the 1200.

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 9:53 am
by David.
Levisp wrote:Blimey £800 on an Akra.
Now over £1,000, https://bmwsupply.co.uk/part/details?se ... w=btdetail

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 10:06 am
by Casbar
I bought mine from a dealer in Germany pre Brexit and it was from memory a lot cheaper than the UK. Also although Akra will sell you a can to fit, which looks exactly the same as the BMW one, only the BMW one is branded HP and etched as such, and is a dealer supplied accessory. So again we could argue BMW would not like any can that is not sold and branded by them. On one site in Italy selling the 1250 Akra they are calling it EU4, so guess mine is an EU3 can only having one pipe exit.

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 10:14 am
by michaelc2710
I also asked BMW and and was told the same thing.
Spoke with Akra and they also told me the same, both cans are identical in length (400mm) with different 'caps'. Both are type approved to ECE R41.


Yes exhausts are designed to handle the gases but the reason the BMW (and others) increased the engine size and added VVT is to help comply with Euro 5. The bigger cc provides better power deliver low down which reduces the emissions, but this in reality is done by the ECU and less by the silencer after the CAT. (this is only an outline of the process and I don't need war and peace on how it works or how I'm wrong)


The Akra upto 2018 was tyre approved at 92dB and from 2019 it was type approved at 89dB, the manufacturer of the exhaust is BMWAG 

Re: Exhaust Flap Valve stuck at around 1000 miles - is this a record?

Posted: Tue Jul 06, 2021 10:26 am
by David.
HP = Higher Price, here is the same silencer for £300 less, https://emlineamoto.com/en/s-b12so21-ha ... gIJdfD_BwE

This is the 1200 can at just less than £700, https://emlineamoto.com/en/spare-parts- ... -hlgt.html