Just wondering about other owners engine performance. I added Akrapovic slip on for sound. Wasn’t looking for more performance and not considering the headers. While in for a service I had the mechanic look into poor performance. When pulling hard like when passing, 4th gear for now, my bike just didn’t seem to pull like I would have expected above 6K. Almost felt like it was t getting enough fuel. Mechanic found nothing wrong. I even asked about the possibility of that exhaust flapper not fully opening. Tested ok. I tested with stock slip back on. No difference.
So, I bit the bullet and scrapped BMWs stock exhaust manifold and went with Akras Titanium headers. Would not have thought this would be the answer but, PROBLEM SOLVED. Not sure if there was maybe a cat restriction or that flapper was not fully opening but the problem is no longer there. It now pulls like a horse as far past 6K as you want to go.


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You can never have too much power!

(08-20-2018, 09:38 PM)Spinner Wrote: So, I bit the bullet and scrapped BMWs stock exhaust manifold and went with Akras Titanium headers. Would not have thought this would be the answer but, PROBLEM SOLVED. Not sure if there was maybe a cat restriction or that flapper was not fully opening but the problem is no longer there. It now pulls like a horse as far past 6K as you want to go.

Hmmm … question is, is it measurably faster than stock.

I have no interest in removing a stock part and adding aftermarket if it does nothing for performance, and that is why I would not buy a slip-on. But a full exhaust including headers … that is another matter. Only problem there is the cost vs actual gain in performance. I rather take that money, but a bit more in and buy another bike.

If not inconvenient, could you take a picture of the Akra headers next to the stock headers so that we might be able to guess at the reason for the re-release of the choke on power?

(08-21-2018, 06:04 AM)Grumpy Goat Wrote:

(08-20-2018, 09:38 PM)Spinner Wrote: So, I bit the bullet and scrapped BMWs stock exhaust manifold and went with Akras Titanium headers. Would not have thought this would be the answer but, PROBLEM SOLVED. Not sure if there was maybe a cat restriction or that flapper was not fully opening but the problem is no longer there. It now pulls like a horse as far past 6K as you want to go.

Hmmm … question is, is it measurably faster than stock.

I have no interest in removing a stock part and adding aftermarket if it does nothing for performance, and that is why I would not buy a slip-on. But a full exhaust including headers … that is another matter. Only problem there is the cost vs actual gain in performance. I rather take that money, but a bit more in and buy another bike.

If not inconvenient, could you take a picture of the Akra headers next to the stock headers so that we might be able to guess at the reason for the re-release of the choke on power?

On a side note, thanks for the Vortex Video. Found it while looking for options to relocate my GPS and the Vortex was the best option. Another member had one so now I’m on my way. Ok. Not sure what you’re trying to determine. A good example I can give was the performance of my 2009 RT. Wheb passing , anytime the RPM got up over 6K you could really feel her kicking in. With my RS it just felt weak. The full Akra took care of that issue and like I said it wasn’t something I needed or wanted to do. I’m sure something was wrong but my shop didn’t find it. Acceleration now very linear as high as you want to take it. I did dyno when finished to make sure I didn’t have any fueling issues and it tested fine. HP increase was very minor. You ne d to increase the air intake and add a fuel controller. After all of that you still won’t get very much. I’m just happy she now runs the way she’s supposed to.

(08-21-2018, 09:34 AM)Spinner Wrote: On a side note, thanks for the Vortex Video. Found it while looking for options to relocate my GPS and the Vortex was the best option. Another member had one so now I’m on my way.

Yes, he told me that he sold it to you. He and I ride together, even if only once a year.

(08-21-2018, 09:34 AM)Spinner Wrote: Ok. Not sure what you’re trying to determine. A good example I can give was the performance of my 2009 RT. Wheb passing , anytime the RPM got up over 6K you could really feel her kicking in. With my RS it just felt weak. The full Akra took care of that issue and like I said it wasn’t something I needed or wanted to do. I’m sure something was wrong but my shop didn’t find it. Acceleration now very linear as high as you want to take it. I did dyno when finished to make sure I didn’t have any fueling issues and it tested fine. HP increase was very minor. You ne d to increase the air intake and add a fuel controller. After all of that you still won’t get very much. I’m just happy she now runs the way she’s supposed to.

I was just trying to figure out what is going on with your bike. I would think that putting on the slip-on should not cause a choking of the engine anywhere below redline. My bike with the stock exhaust behaves like yours does now with the choke point removed. In other words I accelerate through 6k all the way to redline (only a couple of times I've redlined it, mind you) and it pulls strongly and pretty linearly until it hits redline then the rev-limiter kicks in.

(08-21-2018, 12:42 PM)Grumpy Goat Wrote:

(08-21-2018, 09:34 AM)Spinner Wrote: On a side note, thanks for the Vortex Video. Found it while looking for options to relocate my GPS and the Vortex was the best option. Another member had one so now I’m on my way.

Yes, he told me that he sold it to you. He and I ride together, even if only once a year.

(08-21-2018, 09:34 AM)Spinner Wrote: Ok. Not sure what you’re trying to determine. A good example I can give was the performance of my 2009 RT. Wheb passing , anytime the RPM got up over 6K you could really feel her kicking in. With my RS it just felt weak. The full Akra took care of that issue and like I said it wasn’t something I needed or wanted to do. I’m sure something was wrong but my shop didn’t find it. Acceleration now very linear as high as you want to take it. I did dyno when finished to make sure I didn’t have any fueling issues and it tested fine. HP increase was very minor. You ne d to increase the air intake and add a fuel controller. After all of that you still won’t get very much. I’m just happy she now runs the way she’s supposed to.

I was just trying to figure out what is going on with your bike. I would think that putting on the slip-on should not cause a choking of the engine anywhere below redline. My bike with the stock exhaust behaves like yours does now with the choke point removed. In other words I accelerate through 6k all the way to redline (only a couple of times I've redlined it, mind you) and it pulls strongly and pretty linearly until it hits redline then the rev-limiter kicks in.

Exceeding 6K isn’t something most of us normally do or need to do so I’m not sure when it started. Probably going on for a while. First time I noticed it I had added a touring shield. While passing on a pretty good grade in some good wind when I exceeded 6K I noticed the bike just wasn’t continuing to pull like it should. Talked to the shop when for service they found nothing wrong. This went on for a while and the more I looked for the problem the more aware of it I became. No way to know but I strongly suspect something with the solenoid for the exhaust flapper operation. Guess I’ll never really know. Performs just fine now.

(08-22-2018, 09:40 PM)Spinner Wrote:

(08-21-2018, 12:42 PM)Grumpy Goat Wrote:

(08-21-2018, 09:34 AM)Spinner Wrote: On a side note, thanks for the Vortex Video. Found it while looking for options to relocate my GPS and the Vortex was the best option. Another member had one so now I’m on my way.

Yes, he told me that he sold it to you. He and I ride together, even if only once a year.

(08-21-2018, 09:34 AM)Spinner Wrote: Ok. Not sure what you’re trying to determine. A good example I can give was the performance of my 2009 RT. Wheb passing , anytime the RPM got up over 6K you could really feel her kicking in. With my RS it just felt weak. The full Akra took care of that issue and like I said it wasn’t something I needed or wanted to do. I’m sure something was wrong but my shop didn’t find it. Acceleration now very linear as high as you want to take it. I did dyno when finished to make sure I didn’t have any fueling issues and it tested fine. HP increase was very minor. You ne d to increase the air intake and add a fuel controller. After all of that you still won’t get very much. I’m just happy she now runs the way she’s supposed to.

I was just trying to figure out what is going on with your bike. I would think that putting on the slip-on should not cause a choking of the engine anywhere below redline. My bike with the stock exhaust behaves like yours does now with the choke point removed. In other words I accelerate through 6k all the way to redline (only a couple of times I've redlined it, mind you) and it pulls strongly and pretty linearly until it hits redline then the rev-limiter kicks in.

Exceeding 6K isn’t something most of us normally do or need to do so I’m not sure when it started. Probably going on for a while. First time I noticed it I had added a touring shield. While passing on a pretty good grade in some good wind when I exceeded 6K I noticed the bike just wasn’t continuing to pull like it should. Talked to the shop when for service they found nothing wrong. This went on for a while and the more I looked for the problem the more aware of it I became. No way to know but I strongly suspect something with the solenoid for the exhaust flapper operation. Guess I’ll never really know. Performs just fine now.

I went with akrapovic header and left the stock muffler.

(08-23-2018, 12:36 AM)Mark Wrote: I went with akrapovic header and left the stock muffler.

That's one of the more uncommon changes. Noticed any difference?

" First time I noticed it I had added a touring shield." Hey Spinner, possibly unrelated, but my experience with the California Scientific XL screen and the installation of a large touring screen on my brother's Kawasaki Concours produced somewhat similar results. Before we replaced the stock, worn front springs on the Kawi, you could see the effects of the "barn door" screen. Actually compressing the forks 1.5" riding into a headwind! At the road speeds you were describing, you're pushing through quite a bit of air. My RS had no suspension issues, as on the Kawi, but could certainly feel the wind trying to hold you back, seemingly softening the engine response

(08-25-2018, 05:37 AM)Duccrazydave Wrote: ... my experience with the California Scientific XL screen and the installation of a large touring screen on my brother's Kawasaki Concours produced somewhat similar results. Before we replaced the stock, worn front springs on the Kawi, you could see the effects of the "barn door" screen. Actually compressing the forks 1.5" riding into a headwind!

Wow ... never thought of that but it makes a lot of sense. The large "airfoil" in front with an acute angle of attack sloping backwards would cause significant downforce but to deflect the suspension 1.5" ... wow. And that is after the natural tendency of the front to lift with increasing speed!

Naturally that significant downward component would also have a significant horizontal component rearward, opposing the forward travel of the bike hence slowing it down.

I should put my Givi touring screen on the market ... chances are I will never use it. Buffeting and slowing the bike down significantly is a lose-lose situation.

(08-23-2018, 05:33 AM)Grumpy Goat Wrote:

(08-23-2018, 12:36 AM)Mark Wrote: I went with akrapovic header and left the stock muffler.

That's one of the more uncommon changes. Noticed any difference?

It seem to rev quicker through the rev range 6k plus



Mark

(08-26-2018, 11:42 PM)Mark Wrote:

(08-23-2018, 05:33 AM)Grumpy Goat Wrote:

(08-23-2018, 12:36 AM)Mark Wrote: I went with akrapovic header and left the stock muffler.

That's one of the more uncommon changes. Noticed any difference?

It seem to rev quicker through the rev range 6k plus

Interesting you didn’t go with the slip on also. The way you did it though, you got the most gain by un restricting the exhaust and cutting down on a few DBs.
I’ve always wondered how that setup would work out.

Mark

---

(08-25-2018, 05:37 AM)Duccrazydave Wrote: " First time I noticed it I had added a touring shield." Hey Spinner, possibly unrelated, but my experience with the California Scientific XL screen and the installation of a large touring screen on my brother's Kawasaki Concours produced somewhat similar results. Before we replaced the stock, worn front springs on the Kawi, you could see the effects of the "barn door" screen. Actually compressing the forks 1.5" riding into a headwind! At the road speeds you were describing, you're pushing through quite a bit of air. My RS had no suspension issues, as on the Kawi, but could certainly feel the wind trying to hold you back, seemingly softening the engine response

You know, when I first noticed this issue I had added a PUIG Windscreen for winter and touring. Noticed on long rides with wind it really effected my mileage. I’ve since gone back to the original BMW screen. Just have to use good ear plugs. Also thinking about the new Neotec or just a regular full face helmet. My Schuberth ain’t cutting it. Wind noise is killing me.

Took Dave's suggestion and split off the thread to form a new offshoot on Windscreens and wind noise. That topic is always a useful discussion and since one of the RSs very few shortcomings is windscreen and wind noise, that topic deserves its own thread.

(08-20-2018, 09:38 PM)Spinner Wrote: Just wondering about other owners engine performance. I added Akrapovic slip on for sound. Wasn’t looking for more performance and not considering the headers. While in for a service I had the mechanic look into poor performance. When pulling hard like when passing, 4th gear for now, my bike just didn’t seem to pull like I would have expected above 6K. Almost felt like it was t getting enough fuel. Mechanic found nothing wrong. I even asked about the possibility of that exhaust flapper not fully opening. Tested ok. I tested with stock slip back on. No difference.
So, I bit the bullet and scrapped BMWs stock exhaust manifold and went with Akras Titanium headers. Would not have thought this would be the answer but, PROBLEM SOLVED. Not sure if there was maybe a cat restriction or that flapper was not fully opening but the problem is no longer there. It now pulls like a horse as far past 6K as you want to go.


Sent from my iPad using Tapatalk

Does the akrapovic header have a exhaust flapper? If not are there any fault codes triggered when the flapper is disconnected?

(06-02-2020, 03:39 PM)Loady1 Wrote:

(08-20-2018, 09:38 PM)Spinner Wrote: Just wondering about other owners engine performance. I added Akrapovic slip on for sound. Wasn’t looking for more performance and not considering the headers. While in for a service I had the mechanic look into poor performance. When pulling hard like when passing, 4th gear for now, my bike just didn’t seem to pull like I would have expected above 6K. Almost felt like it was t getting enough fuel. Mechanic found nothing wrong. I even asked about the possibility of that exhaust flapper not fully opening. Tested ok. I tested with stock slip back on. No difference.
So, I bit the bullet and scrapped BMWs stock exhaust manifold and went with Akras Titanium headers. Would not have thought this would be the answer but, PROBLEM SOLVED. Not sure if there was maybe a cat restriction or that flapper was not fully opening but the problem is no longer there. It now pulls like a horse as far past 6K as you want to go.


Sent from my iPad using Tapatalk

Does the akrapovic header have a exhaust flapper? If not are there any fault codes triggered when the flapper is disconnected?

No flapper or cat in header. Disconnect cables from flapper motor and leave motor in place no faults.

(06-06-2020, 11:40 PM)Mark Wrote:

(06-02-2020, 03:39 PM)Loady1 Wrote:

(08-20-2018, 09:38 PM)Spinner Wrote: Just wondering about other owners engine performance. I added Akrapovic slip on for sound. Wasn’t looking for more performance and not considering the headers. While in for a service I had the mechanic look into poor performance. When pulling hard like when passing, 4th gear for now, my bike just didn’t seem to pull like I would have expected above 6K. Almost felt like it was t getting enough fuel. Mechanic found nothing wrong. I even asked about the possibility of that exhaust flapper not fully opening. Tested ok. I tested with stock slip back on. No difference.
So, I bit the bullet and scrapped BMWs stock exhaust manifold and went with Akras Titanium headers. Would not have thought this would be the answer but, PROBLEM SOLVED. Not sure if there was maybe a cat restriction or that flapper was not fully opening but the problem is no longer there. It now pulls like a horse as far past 6K as you want to go.


Sent from my iPad using Tapatalk

Does the akrapovic header have a exhaust flapper? If not are there any fault codes triggered when the flapper is disconnected?

No flapper or cat in header. Disconnect cables from flapper motor and leave motor in place no faults.

Will be fitting NoCat headers to my 15RS soon. Do you have the Akra baffle in or removed from your slip on. I am expecting no cat and no baffle may be loud.

About to find out. Just finished fitting a set of MIVV headers that I bought from Italy (nocat). They have neat little brackets pre welded on to attach the no longer used flapper cables. I have also gone with the stock muffler for now even though I have a AKRA slip on to try later.

That's my configuration.