R12S - full exhaust system without any special chip

[signit98]

...if it does not work for the 12S, I'll buy it from you for the GS...

[kocook]

The Akrapovic full system is truly bolt on. Adds about 5 hp, but more importantly smooths out the power delivery and decreases weight by a few pounds. This is dyno tested before and after. You will need nothing else.

However, if you wish to pick up about 2 more HP, buy the Unifilter from BMW Motorcycles Atlanta. Also, dyno tested. No change in fuel/air mixture needed.

[Riv]

Originally Posted by kocook

The Akrapovic full system is truly bolt on. Adds about 5 hp, but more importantly smooths out the power delivery and decreases weight by a few pounds. This is dyno tested before and after. You will need nothing else.

However, if you wish to pick up about 2 more HP, buy the Unifilter from BMW Motorcycles Atlanta. Also, dyno tested. No change in fuel/air mixture needed.

What you're saying about Akra full have you read it or have you tested yourself?

What is Unifilter?

[kocook]

Originally Posted by Riv

What you're saying about Akra full have you read it or have you tested yourself?

What is Unifilter?

SJBMW did a before and after dyno run when they installed the Akrapovic full system on my new R1200S. Chris H. wanted to do that on a new R1200S with no mods to isolate any performance change, since he was considering swapping the headers on the race bike from Remus to Akrapovic. The Remus has not held up well to the rigors of racing.

Then, several months after riding the bike, I did a before and after dyno run when I swapped out the stock air filter for the Unifilter air filter. I literally installed the filter with the bike on the dyno between the runs. The unifilter air filter is imported by BMW Motorcycles of Atlanta. You can get one from them.

BTW, the increase in HP is not just at the peak RPM. For both mods, the performance boost was pretty much across the power band, with the exhaust mod having the added benefit of eliminating the significant power/rpm ratio dip in the 4K to 6K rpm range on this engine.

Also, I do not personally know what would be the effect of just adding the air filter, because I added it after I added the exhaust. However, if you mimic what I did, you will likely get very similar results.

Finally, beware any claims which do not have before and after dyno runs to back them up.

Hope this clarification helps you.

[Riv]

Originally Posted by kocook

SJBMW did a before and after dyno run when they installed the Akrapovic full system on my new R1200S. Chris H. wanted to do that on a new R1200S with no mods to isolate any performance change, since he was considering swapping the headers on the race bike from Remus to Akrapovic. The Remus has not held up well to the rigors of racing.

Then, several months after riding the bike, I did a before and after dyno run when I swapped out the stock air filter for the Unifilter air filter. I literally installed the filter with the bike on the dyno between the runs. The unifilter air filter is imported by BMW Motorcycles of Atlanta. You can get one from them.

BTW, the increase in HP is not just at the peak RPM. For both mods, the performance boost was pretty much across the power band, with the exhaust mod having the added benefit of eliminating the significant power/rpm ratio dip in the 4K to 6K rpm range on this engine.

Also, I do not personally know what would be the effect of just adding the air filter, because I added it after I added the exhaust. However, if you mimic what I did, you will likely get very similar results.

Finally, beware any claims which do not have before and after dyno runs to back them up.

Hope this clarification helps you.

Thank you very much for having told your experience, very authoritative i think.
At this moment i've installed a K&N airfilter and the Akrapovic Slip-On, but with the original catalyst and in fact the engine is overall enjoyable, "round", powerful above 6000 (as before), but between a little bit flat between 4000 and 6000.
So, I think that what akrapovic declare is almost true.....and i'm happy because i don't wont to have to remap any sort of chip...
Now, last think to digest is the price...~1700€ for Racing System and ~2200€ for Evolution System!
Nobody knows wher to buy in europe at good price? Also used parts...perhaps from any Bmw team

[kocook]

Given those prices, you may consider purchasing from a US vendor and shipping to you. The Akrapovic is a simple install. Make very sure you clean the pipes per the instructions, though. If you don't you will have hand prints permanently burned into the surface.

[OwenM]

I replaced the BMC cotton wire filter (similar to K@N) on my “rapid biked”, full Remus system equipped, dyno tuned R1200S with a Unifilter foam filter and it certainly did make a difference.
The engine runs smoother, especially at low rpm, and the mid range sag at 5000-6000 rpm is reduced.
I am confident the Unifilter filters more effectively as well.
Unifilter don’t list a R1200S filter, but the GS filter is the same and fits perfectly.

[kocook]

I did not see the R1200GS listed either. Got a part number for that?

[OwenM]

Unifilter now list the R1200S, along with most of the R1200 models (same filter).
Part number is NU 7305KIT.

Go there and search for R1200.

http://www.uniflow.com.au/

BMW Atlanta sells these in the US.