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K&N Air filter

teleman609

teleman609

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Anyone currently using a high flow air filter like K&N or DNA
any improvements?
Wondering if it's worth the $$ on the c400GT
I've had them in other Motorcycles and cars in the past.
 
teleman609 said:
Anyone currently using a high flow air filter like K&N or DNA
any improvements?
Wondering if it's worth the $$ on the c400GT
I've had them in other Motorcycles and cars in the past.
Click to expand...
I've been on the forum for about two years now, and I don't recall reading about anyone's doing that on a C 400 GT. And I'm familiar with folks using K&N air filters from reading about it on forums dealing with other bikes I've owned over the years. Of course, maybe your question will get someone who HAS done that to speak up.

In terms of the USA, note that the C 400 GT has been sold here for only about two+ years now. I mention this because that would put these scoots still within the warranty period (unless someone has ridden theirs a LOT of miles), and going to a higher-flow air filter might void the warranty. I don't know that for a fact, but that's my guess. Given that I've already had one C 400 GT replaced by BMW because of an engine malfunction, I'm particularly gun-shy of messing with anything that might void a warranty. Of course, I suppose you could just replace the air filter with a stock one before any service or warranty claim, but who knows what the ECU is keeping track of.

Anyway, that's just me, but I thought I'd point it out, i.e., such a change might be more appropriate for post-warranty ownership. In the USA, I don't think there's a lot of such ownership, but perhaps in Europe and elsewhere some folks have added K&N stuff to older C 400 GT or C 400 X models.

Interesting question, certainly.
 
Bill, thank you for your view on this subject. You do make very good points about the warranty and the possibility of the ECU picking up any changes.
I was curious to see if anyone has done it out there yet. Let's see what this post would bring, hopefully we can get someone that has done it.
 
MAC400GT said:
Yep, I got the DNA Filter... I also got the Akrapovic Exhaust installed and between these two upgrades the increase in HP is defiantly noticeable.
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That is actually very interesting. I never would have guessed that at all. On the exhaust, it seems that most are reporting improved performance. It's just not something I do. Thanks for sharing and adding to the data on this!!
 
This is from the K&N psite:

- WILL USING A K&N® REPLACEMENT AIR FILTER VOID MY FACTORY WARRANTY
No. In the United States, in order for the manufacturer of a warranted product to void or deny warranty coverage of a repair due to the use of an aftermarket part, the manufacturer must provide proof that the aftermarket part is the cause of the necessary repair. These rights are protected under the Consumer Products Warranty Act of 1975 (also referred to as the Magnuson-Moss Warranty Act).
 
I used a K&N high flow oil filter on my Indian Challenger and I thought there was an improvment on the smoothness of the motor. The bike had more power than I ever needed so that was never an issue. But I would try one on the C400gt for the smoothness alone.
 
StrangeCloud said:
This is from the K&N psite:

- WILL USING A K&N® REPLACEMENT AIR FILTER VOID MY FACTORY WARRANTY
No. In the United States, in order for the manufacturer of a warranted product to void or deny warranty coverage of a repair due to the use of an aftermarket part, the manufacturer must provide proof that the aftermarket part is the cause of the necessary repair. These rights are protected under the Consumer Products Warranty Act of 1975 (also referred to as the Magnuson-Moss Warranty Act).
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Yup. I've learned a lot about this lately. Definitive causal relationship is the primary operator in warranty denials; establishing that relationship, between the aftermarket part, additive, fluid, whatever and the failure being denied under warranty must be definitive and supported in fact before any dealer or manufacturer can deny a covered repair. Well, they can deny it without the fact-based support, but it is not worth it to do so. Altering the ECU, you're going to be denied as the owner is presumed to have placed the vehicle out of operating specifications and a failure should be expected. Wrong oil? Maybe. They would have to prove the incorrect oil was the cause of the failure, not just that the wrong oil was used. Adding an air filter, not a chance in hell on a nine grand scooter. The support they would need from engineers, laborer's time, legal, admin prevent manufacturers from going down this road. A $30K engine or a $100K lemon claim, they might give it some thought. I am not a lawyer but have had recent conversations with lawyers about this exact topic but regarding fuel additives.
 
mzflorida said:
Yup. I've learned a lot about this lately. Definitive causal relationship is the primary operator in warranty denials; establishing that relationship, between the aftermarket part, additive, fluid, whatever and the failure being denied under warranty must be definitive and supported in fact before any dealer or manufacturer can deny a covered repair. Well, they can deny it without the fact-based support, but it is not worth it to do so. Altering the ECU, you're going to be denied as the owner is presumed to have placed the vehicle out of operating specifications and a failure should be expected. Wrong oil? Maybe. They would have to prove the incorrect oil was the cause of the failure, not just that the wrong oil was used. Adding an air filter, not a chance in hell on a nine grand scooter. The support they would need from engineers, laborer's time, legal, admin prevent manufacturers from going down this road. A $30K engine or a $100K lemon claim, they might give it some thought. I am not a lawyer but have had recent conversations with lawyers about this exact topic but regarding fuel additives.
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Useful info from you guys. Thanks, and I sit corrected.
 
wspollack said:
Useful info from you guys. Thanks, and I sit corrected.
Click to expand...
I disagree that you were corrected, Bill. When warranty coverage is in play (important to the owner), and an owner is considering modifications, they should also consider if the modification will void the warranty; because it can. In most cases it is cost prohibitive for a manufacturer to do so, but they can, and do, from time to time. You are definitely a deep thinking motorcyclist and were spot on in encouraging consideration of downstream impact of modifications and alterations.
 
Here is what my experience on C650 tells me.
I have bought an aftermarket exhaust by GPR, called Furore 4 Evo.
When I replaced the air filter with K&N, the fuel consumption jumped up to 8L per 100km, without significant performance feeling, only more noise. The air flow is too unrestricted, showing too much O2 on that sensor so ECU injects even more fuel, but I guess at same pressure it is not fully burnt or something. It is not for nothing that KTM engines have dual sparks per cylinder, getting close to 96hp from about same volume.
With a stock exhaust, K&N makes sense but that is not my case.
 
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