K&N air filter for yzf 450

K&N is supposed to come out with a filter for the yzf 450,anybody have info on this??? I put one in on my yfz 450 quad and it really made a big difference! You dont see many guys using them MX, :cry: but I beleive they bring in more air than the traditional foam filters........Thanks Matt

If it's the same design as the 250F's that goes inside the airbox, it sucks. The stock filter flows more air than the K&N does.

If you want better airflow, use a 125 filter cage or cut the screen out of the 450's and use a twinair backfire filter. And cut the rear wall of the airbox down flush with the fender.

Thanks for the advice!! Im surprised that the K&N doesnt breathe better.......Matt :cry:

It's the design that killed it. Imagine the old style air filters on cars. The ones that were in the shape of rings that laid on their sides and had the air cleaner cover cover up the donut hole on top.

The k&n did the same thing. Where the stock filter can take air thru the front as well as on the sides, the k&n can only take air in on the sides. It forces the air to take too many turns getting into the carb and that slows it down enough to kill WOT performance.

The ones they use on supermoto is better, but you have to get rid of the airbox to use it.

That makes sense!! Do you think the uni or twin air foam filters are any better than the stock :cry:??Matt

I have always used twinair's, so I cant speak for uni. But I do know that twinair uses an adhesive on their foams that isnt affected by gasoline, I dont think uni can say the same thing.

The twinair backfire filter is great for getting more hp, it's the only one I use on both yz250f's and now on the 450 as well. As long as you clean it after every ride it does great.

I put a K&N in my 00426 and noticed an improvement over the TwinAir. Don't have test data to confirm... but for me... worth it in performance, maintenance and longevity. :cry:

Where did you feel it made a difference over the twin air??

Matt :cry:

Do you clean your filter with gasoline?? Im going to look into that backfire filter!!Thanks for the tip.........Matt :cry:

The last thing in the world I would subject my bike to is the pathetic filtering that a K&N provides. It is amazing how much dirt they let through. There is a reason they flow so much. :cry:

Let me guess you fried your motor because of one!!! Matt :cry:

I clean the twinairs with gas. look on twinairs site for the power kit, on that page they list the filter separately.

Here's a pic of it. The filter part number is 152313, you can either use their cage, or one from a yz125. It will fit the 450 too.

backfire%20cut-a-way.jpg

From the looks of it they added the backfire stuff and didnt replace the inner dense foam with it. I was under the impression it replaced it. Good to know that. Here's the llink to it, http://shop.twinairusa.com/catalog/product_info.php?cPath=2_9&products_id=263&osCsid=b56b056d54a13c57688ff51f974f8a18

I have always used twinair's, so I cant speak for uni. But I do know that twinair uses an adhesive on their foams that isnt affected by gasoline, I dont think uni can say the same thing.

The twinair backfire filter is great for getting more hp, it's the only one I use on both yz250f's and now on the 450 as well. As long as you clean it after every ride it does great.

The adhesive on the uni's gets eaten alive by gas. I now have to get a new filter because of it.

I have a K&Nair filter onmy yz450f and noticed more air flow quicker throttle responce. I never had problems w/dirt getting past it like others claim?

Do you have an 04 yzf 450?? I was told the K&N filter was not out yet!!Matt :cry:

Thanks for the link!!Matt :cry:

In the first place, as 'Rider pointed out, if you think of the YZ450 filter as roughly cylindrical, The K&N breathes only through the sides, whereas foam filters pass air through the closed end as well. This is at least partially made up for by the fact that the K&N media flows much more air than foam for a given area, but it has much less area to work with. Only by comparing properly oiled elements on a flow bench would you be able to know for sure which one flowed more net air.

Secondly, they filter just fine, IF they are properly oiled, but getting that done is not as simple as with foam, and that's what leads to complaints of poor filtering. Because of the nature of the media, you can't work the oil in by hand to insure full and even distribution. The oil has to be sprayed, brushed or poured down into each pleat or a "hole' will exist. Unoiled media filters poorly.

On the other hand, they're flame proof, and cost less than the Twin Air flame proof foam, so you can substitute a YZ250R filter frame and get rid of the backfire screen. I haven't seen a price on the TwinAir element by itself, so the price difference may not be that great, but unless TA charges a lot more for their filter frame than Yamaha, they're pricey.

For the sake of the survey, I use White Bros Powerfilters. They work.

the twinair backfire filter runs at $40 or less, depending where you get it. You can either buy twinair's filter cage, or a cage from a yz125, or just remove the screen from your own.

You do away with the filter cage from the factory all togethery using the k&n it's rigid and serves as it's own filter cage. It comes with a lid for the open end. I think I paid $50 for the k&n but that was when they first offered them. I dont know what they run now. I do know they filter fine collecting dust sitting on the shelf in my shop. :cry:

Let me guess you fried your motor because of one!!! Matt :cry:

Nope, as I have said, I have never and will never put one on my motorcycle. I used to use one on my truck that was properly oiled and used 2 different pre-filters and when I checked it at around 10,000 miles I found lots of fine dust and my silicon levels were through the roof. Once I install the twins on my truck I will be forced to use another one since there is no paper element that flows enough air but you can bet I won't use K&N. It will be AFE for me.

Anyways, if they are letting dirt through in a non-dusty environment then what will happen if it is on a dirt bike where the dust can get so thick that you can't see. Sorry, I will stick with what works. Besides, cleaning a K&N is much more of a pain in the ass then cleaning a foam filter. BTW, Twin-air filters are what I use.

I've used stock, UNI, and the K&N. I am very happy with the performance of the K&N and have no complaints. I find it easier to clean and re-oil and I like the way it seals to the air box better than the foam filters. I have gotten easier starting and quiker throttle response. I have found no differance WOT either. JMO

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