AC Schnitzer & KN-Filter on 09' GS

[TSE_DK]

Hi.. I've just picked up a 09 GS from the dealer and so far I really like it. Before buying it I had a testride on a 100% stock 06' with my gf on the back. Both machines are ofc brilliant- and I'm aware that my 09 has 5 bhp more stock than that of the 06.
Still I cant get it out of my head- the feeling that my 09 seems to pack a considerably larger punch, especially with passenger.

My 09 is fitted with a stainless AC Schnitzer RV1 exhaust, it still uses the stock headers tho. Also there is a KN-filter installed- type BM-1204. And as far as i know that's it.

My question is mainly if anyone here know what gain in performance such a combo would result in? And could it really be the reason why it feels stronger and not just the sound fooling me..

I'd also like to hear if anyone in general has some experiences with AC Schnitzer equip

Thanks in advance... Tommy

[marc]

Welcome to the forum.

Don't know anything about the AC Schnitzer RV1 exhaust, however several folks notice a difference when changing cans. The interesting part is that while a difference is often felt with the owner commenting about things like "better lower end" the few who've actually put the bike on a dyno find little difference in the end numbers. What does sometimes happen is that the torque curve is moved. If there is more power where you want it, even if less total power available, then I guess that is a good thing.

Keep in mind, too, that there is often a difference from bike to bike. Some just seem to run better than others. Maybe you got one of the great ones.

As for the K&N: Breathing hasn't been a reported issue with these bikes. The K&N propensity for letting dirt past the filter, on the other hand, is. I'd not use one myself. Here's an example of what a K&N let pass on an a different bike: http://www.largiader.com/shop/gallery/kandn.jpg That's from http://www.largiader.com/shop/gallery/ where Anton's comment is "I see this more often with K&N filters. Dirt on the inside is not cool."

If you often ride in dirty, dusty, and wet conditions I'd consider the Uni filter and pre-filter. If you spend most of the time on the road the stock filter works quite well in letting air in and keeping dirt out.

[TSE_DK]

Thank you for the welcome

Surely my GS runs fine- the engine is hardly ever been cold since ive picked it up
-What would have been interesting for me though, was if I had also ridden a stock 09 which I haven't. So the question still remains.. if the Schnitzer & KN combo does it any good.. and if we drop the specifics- what is the approx hp gain when mounting a good aftermarket can like Akrapovic or Remus.. ?

I think you are right about the torque curves tho. The area where it feels as though my own is stronger shows best at around 3500 to 5000 rpm though admittedly I think its easier to detect differences there as opposed to the high end. I only had a small stretch of local road to serve as test-track.

The picture do raise some questions. Truth be told I've heard such stories before and guess only thing to do is to open up the bike and take a look at it. If its not as its supposed to be the KN is out of there.

Thanks

[Doc Chex]

Originally Posted by TSE_DK

................
what gain in performance such a combo would result in? And could it really be the reason why it feels stronger and not just the sound fooling me..
...............

Hi Tommy,

it´s hard to say which bike is the better one and which components have positive influence.

My friend has a R12R with 109PS, Wunderlich Blue Filter equal to the K&N and an AC Schnitzer. My 07 GS with 98PS has just the Blue Filter, that´s all. In several trials we couldn´t find a deviation between the bikes. The acceleration is the same and top speed too.

My friend installed the AC Schnitzer because it looks much pretty than the original and it sounds better without to be agressive noisy. And from the back it looks pretty good.

In Germany they checked out 25 exhausts. Just 4 exhausts have a positive influence to the engine power. All the rest destroy power but make much more noise.

I guess you can find the report on motorradonline.de (click it)

I made the experience that an aggressive and loud exhaust makes me nervous and reduces my concentration when I want to drive a hot wheel. High engine speed like 10k or more rpm I also dislike. On the other hand I don´t want earmuffs. I can´t understand people installing loud exhausts and wearing ear protectors because the exhaust is to loud

At the same time I couldn´t find a deviation to the 08 modell. So I decided I will the bike leave in serial condition.

In my opinion the K&N is not for heavy duty because it lets pass to much respirable dust, but for moving on the road it´s ok. In any german motorcycle magazine they showed diagrams and comparisons of different brands and in the necessary and important requests the K&N never passed the average.

[TSE_DK]

I see the point Doc..

The more I've been reading the closer I've come to the same conclusion- which is.. changing the end muffler alone doesnt result in a noticable performance gain if any at all, and should mostly be done if looks and sound are high on the wish list. Personally I'm not disappointed in the aftermarket exhausts- I'd much rather see this as a testament to the quality of the stock equipment.

On a finishing note.. I will leave my AC Schnitzer on- but now its not caused by illusions of higher bhp's but instead for looks and the crisp sound it produces.

About the filter.. I've been giving it a lot of thought. Though the bike is and will be used mainly as a "on-road" tourer I cannot see the point of having a filter that does its job worse than the original part- especially if it doesnt result in a massive bhp boost. Luckily the original filter came with the bike, so I guess I'll switch it out with the KN thats on at the moment to see how thats going to work.
- If not for anything.. then for sleeping better at night..

Thanks for your inputs
Tommy

[Doc Chex]

Hi Tommy,

my consideration to install the Blu Filter were that it´s built of cotton instead of paper. The paper can absorb air huminity and this makes the breathing of the engine difficult - result is the loss of power. The Blue can be used for the lifetime of the bike, you can clean it and reinstall as well. I guess after 60k km the costs of the paper filter are equal. Normally the Blue has to be cleaned at 80k for the first time. The gains are now on your side.

First I tried the K&N but I couldn´t close the airbox because the frame of the filter was too rigid and I could put in the taper keys just the half way

The frame of the Blue is smooth and it´s no problem to install. The properties are the same and the costs too.

By the other hand your are right. It needs more than to change the muffler to get more power. If you want to tune up the engine on it´s best you have to install:

• Blue Filter, intake air duct, power command with individuell mapping, excellent exhaust, better camshaft would be ideal.

A good shop makes a incoming diagram and a outgoing diagram. The new mapping is created on the engine test bench.

This coul be a nice activity for the wintertime

Or you take a Big Bore (click it)