Euro 4 Exhaust Note

[Neil W]

After running the old 2014 gsa for 3 years and 6 continental trips I am away on the 2018 model at the moment.
Using bmw panniers off the old bike but I have noticed that unlike the old bike the new one has an uneven pulsing exhaust note at autobahn cruising speeds from 60mph up to 90mph plus.
It is very intrusive and odd to say the least , it sounds like a multi engined piston engined aircraft when the motors aren't in synch.
Just wondering is this normal on the euro 4 models as it is bloody annoying, if it is down to the exhaust I will stick on a standard can from a euro 3 bike

 

[Deleted account 191119001]

Have a standard can Euro 4 on my 2017 and no problems or weird noises from the can.

 

[malcopopolo]

it will be the strangled en#missions or the exhaust flap is sticking slightly and not fully opening

 

[Deleted account 191119001]

it will be the strangled en#missions or the exhaust flap is sticking slightly and not fully opening

That could well be the problem, I put some Anti seize nickel high temp inside the header where the exhaust flap is, for the just in case scenario.

https://www.dittmar-sba.de/WEICON-Anti-Seize-ASN-120-P-Nickel-Spezial-26050012.html

 

[Boxerlust]

To my knowledge the factory EU3/Eu4 slip-ons are identical except for the stamping.Only difference the catalytic converter on the EU4 is bigger.
I would buy a Akra EU3 pipe,take the DB-killer out and problem solved...
All you have to decide if you like the black or natural TI better..

 

[Matty589]

I had a 2016 GS (Euro 3) and now have a 2018GS (Euro 4) and both engine and exhaust sound identical to me. Maybe the 2018 is a touch smoother but if it is, it’s hardly noticeable. Still sounds like a bag of spanners in a cement mixer!

 

[Boxerlust]

Matty since you can compare how do you rate the gearbox and engine power;EU3 vs EU4 ?

 

[CPJS]

My '17 euro 4 bike is far more noisy with the varios on, the '14 euro 3 bike made no difference whether the varios were fitted or not. Both make the same amount of noise witout varios.
Power the same on both bikes, gearbox much, much better on the '17 bike

 

[Matty589]

Matty since you can compare how do you rate the gearbox and engine power;EU3 vs EU4 ?

The engine feels very similar, maybe a little bit less rattly. gearbox feels a touch smoother and gearshift assist is a bit smoother too - but overall it’s a sight improvement rather than a revolution. I actually find I much prefer my RS, which is Euro 3 but has a lovely gearbox, slick GSAP and less rattling, and a super comfortable riding position. I may even put it up for sale but it’s nearing the end of summer holidays so I may keep it over the winter and see how I feel once it has a few thousand miles as boxer engines seem to take about 10,000 miles to loosen up and feel smooth.

 

[CPJS]

After running the old 2014 gsa for 3 years and 6 continental trips I am away on the 2018 model at the moment.
Using bmw panniers off the old bike but I have noticed that unlike the old bike the new one has an uneven pulsing exhaust note at autobahn cruising speeds from 60mph up to 90mph plus.
It is very intrusive and odd to say the least , it sounds like a multi engined piston engined aircraft when the motors aren't in synch.
Just wondering is this normal on the euro 4 models as it is bloody annoying, if it is down to the exhaust I will stick on a standard can from a euro 3 bike

I carried my euro 3 can over to the euro 4 bike, it is noisier on the euro4 bike with the varios fitted, something to do with the varios bouncing the noise around i think.
I don't know why it happens, all the bits from my '14 bike were carried over to the '17 one so the bikes should be the same.
Just had a thought, both bikes were hilltopped, the fuelling on the euro3 bike was a lot smoother with a linear graph reading compared to the euro4 bike's more restrictive ECU, maybe that has an effect on the exhaust pulses. The fuelling difference between the two bikes is between 5 and 6000rpm where the '17 bike goes a bit vague.