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I need help putting this topic to rest once and for all...

Twin Air advertises that their Air Filter is Backfire-Resistant but UNI does not.

What are the facts on removing the Backfire Screen and replacing the Air Filter with either a UNI or Twin Air?

Which Air Filter brand is really the best?

Is it true that the White Bros. brand Air Filter is manufactured by UNI?

If using a Non-Flammable Oil, is a Backfire-Resistant Air Filter really necessary?

I know Maxima Air Filter Oil is Flammable, as it states that right on their website, so which brands of Air Filter Oil are Non-Flammable?

Is a K&N Filter more Backfire-Resistant than a standard Foam Air Filter because it is cotton gauze based and that is why K&N doesn’t need to advertise that their Air Filters are Backfire-Resistant and Twin Air does?

Thanks in advance for your input!

I use a Twin Air that does not have the fire-retardant layer. I also use No-Toil which isn't flammable. I will probably change to the flame retardant filter the next time I buy one, just as an extra precaution.

I can't answer all of your other questions. You are likely to get a lot of personal opinions on which is the best. I bought my bike from a guy that was a Baja racer. He was using Twin Air and No-Toil... that was good enough for me.

Joe

I think it is April '07 MXA that has an article comparing after market bolt-on mods for a CRF using a dynamometer. Removing the backfire screen had zero measurable effect on Hp or torque at all RPM ranges. They stated that "some riders claim a little more low end snap with backfire screen out." We run Twin Air backfire resistant air filters and Twin Air filter oil with the screen out because my teenagers "think" it makes the bike faster. Good enough for me as I have not yet heard of a CRF catching fire.

it's very unlikely to backfire through the carb. the popping/"backfire" that most talk about is occurring through the exhaust. even still i use the powerflow replacement filter and system. i didn't read the mxa article but i would be curious if they rejetted after removing the backfire screen. if not i am not surprised that they didn't see any gains. the idea is more air in allows you to put more fuel in to maintain optimum air/fuel mixture. if you just put more air in then you'll likely not see more gains.

having said that, even if their were no hp gains, the throttle response with free flowing filter systems is improved. with the twin air powerflow systems another advantage is easier install and removal of the filter/cage assembly and a positive fit that doesn't require rim grease. for me this along with throttle response alone are worth the price of admission.

ken

fbr wrote:I think it is April '07 MXA that has an article comparing after market bolt-on mods for a CRF using a dynamometer. Removing the backfire screen had zero measurable effect on Hp or torque at all RPM ranges. They stated that "some riders claim a little more low end snap with backfire screen out." We run Twin Air backfire resistant air filters and Twin Air filter oil with the screen out because my teenagers "think" it makes the bike faster. Good enough for me as I have not yet heard of a CRF catching fire.

Did the article say what mods they did and what were present at the time of the dyno testing? I suspect they are absolutely correct if all they did was take a stock bike and pull the backfire screen.

Joe

Did you guys have to re jet after removing the backfire screen? I posted this question under 250r but wanted to make sure you saw it. Thanks

I re-jetted, but I also opened the airbox at the same time.
Joe