This needs to be a sticky. It's a bit of an angry post at K&N but with very good reason.
This story began quite some time ago when I purchased a K&N filter which I ended up returning. As anyone who has tried to fit one of these will know, they don't fit. The filter is in a flexible rubbery mount rather than the rigid metal. It is also quite a bit too large, as you can see from the photo labeled "comparison size" In the gallery I link to here...
https://postimg.org/gallery/3icpf2axy/...in another image labeled "doesn't fit" you can see what happens if you try and jam it in, because it's too large and rubbery it gets pushed away from the seal, thus letting dirt into your engine. Compare the OEM filter in the image labeled 'OEM fit'.
Now the reason why I think this is a very big deal is because we have two bikes a GS500 and the Savage, they are both ridden in the same conditions which are generally good roads. The filter on my GS gets grubby but it never has any sand (or small birds) caught in it, I do get some sand around the bottom near the chain but none anywhere near the filter.
The reason I mention this is because after removing the Savage filter it has a lot of sand and bits of other stuff caught in it as you can see from photo labeled "IMG 1169", this is AFTER a lot of more sand had already been removed. Now inside the air box where the filter lives it is spotlessly clean, so there is not leaking anywhere, all this sand must be coming straight down the snorkel or somewhere. It's a good thing the OEM filter fits properly because this much sand would be a bit problem eventually.
Because both bikes are ridden in the same conditions and only the Savage has sand and other debris in the filter I can only conclude that due to the design it is more prone for sand to be whipped up from the road and channeled into the air box.
So a badly fitting filter in your savage air box, is a VERY BIG DEAL, in my opinion.
Why have K&N made a filter that doesn't seal and worse done it on a bike that requires a very good seal. I don't know and they won't tell me because I've written many emails to them, and they have proven themselves to be complete and total ASSHATS, they kept asking me for more details, and when I supplied them, they stopped responding.
So I wrote again to a different person, same thing, they just frikken ignored me. I tried a third time with no response. They just don't give a f*&%.
I bought a new Hi Flo filter which has three times the pleats of the OEM, so I could rebuild the old one like Old Feller did in the tech section, however I'm going to use proper filter foam and the proper oil. I managed to get a big square of the correct filter urethane foam for free, it's a bit thick but the local bike shop told me that is good because if you squash it down to half the thickness then it actually passes more air, it's what they do for the filters they use.
I bought some stainless steel mesh from eBay but as you can see in one of the images, it was supposed to be 30 x 30 cm but it came folded! I asked for a refund because it's now useless. So I'm going to try and make some sort of a cover and have it welded with a hinge of some sort so that I can replace the oiled filter easily when the time comes.
So if you're thinking of using the K&N filter do be aware that it won't seal and even if you try and build up the plastic with epoxy resin as some have tried to do, how confident are you that it is sealing properly because if it isn't it's going go suck sand in.
Below is some email correspondence.
This is the first email I sent them...
Just got your SU 6595 for my Suzuki S40, I was trying to install it the wrong way at first as I assumed the cutaway part was for the metal retaining plate. However once I realised my error and oriented it the correct way, I could not get it to seal properly because the shell is bendy and as you can see from the photo it is way too big and it presses against the bottom of the airbox and also the top of the airbox what that does is make the filter bend backwards because the top of the airbox is angled and it makes it pull away from where it is supposed to seal!
Why? WTF etc.
They did not answer I asked for a reply and they again did not answer so I sent them this...
Hi, I have already inquired about this issue but I have received no reply yet.
I bought the correct air filter for the suzuki savage however it does not fit. The instructions say to put some k&n sealing grease on the rubber lip because it’s important to get a good seal or damage can result.
OK, so why is the filter so big that it hit the top and the bottom of the airbox which slops backwards and thus pushes the top and bottom of the filter away from the sealing lip?
I have seen that some people on forums have taken to building up the airbox with epoxy resin so that it contacts the seal better.
WTF K&N?
See photo enclosed.
They eventually wrote to me and asked for more information which they then ignored so I wrote to them yet again....
I’ve written twice now, you guys asked for more information which I sent but still no response. Is this as far as it goes.
I bought a k and n filter for my S40 and there’s no way it fits, it’s obviously too large. Do you want to make any sort of comment or will I just take it that you don’t give a crappity smack?
Thanks.They asked me to call them and I wrote back...
I’m in Australia so there’s no point calling. I’ve sent you the photos, it’s pretty obvious that the drop in filter you have for the Suzuki S40 is too large for the airbox, it’s too large by a long way. It has caused me considerable inconvenience as well as losing the cost of the return postage of $20. I’m looking for an explanation as to how you can be selling this filter that is so obviously too large. See my previous emails for the photos.
Thanks