I'm thinking of buying it for my 400ex. But I see so many people write, that it's crap.
I do not ride in dusty areas. I ride in wet and hard sand, little mud and I sometimes drive through not very deep rivers. The country where I live, it's almost only wet all the time. But of course dry days too. So could I use a K&N Air Filter for this type of riding? and how often should it be washed?

One more question, I saw something called Sparks Timing Key over the internet. What does it do? Will it only help or does it have cons too?

Thanks.

 

I looked into the K&N for my bike 05 Sp 500 and I decided to go with UNI filter instead. Great filter and easy to clean.

 

You picked the best filter for any atv! I've seen too much damage cause by neglected K&N filters,even with socks on they breathe in too much dust for off road use and goes straight to the piston.Uni is especially good for the old 2 strokes that are crucial on having clean air! That's why almost all 2 stroke dirt bikes have foam filters also! K&N is fine for cars on nice clean highways! I know others may disagree,but just from my experience and also just my OPT

 

Thanks Old Polaris Tech, my thoughts exactly!

 

K & N's do work great, but all it takes is ONE day of dusty conditions and your motor is hurt. Get a UNI.

 

Whatvif I'll use an outerwear?

 

In the conditions you ride IMHO you will be fine. You should have the outerwear on it anyway because of the water you ride in. Like others have said the Uni is a good filter from what I have read.

About the key. Yes it will help. It's an advance key that will advance your ign timing. It will make the engine a little more snappy because of it.

Like most things in life there is always cons. If you advance your engine too much you can get detonation or ping. Around sea level and on hot days this will be worse. The cure for this is to use a higher grade of gasoline. Most key makers will tell you to go one or two grades higher in gasoline grade to prevent detonation.

I haven't figured out why all things that taste good are bad for you? Take bacon or ice cream. They are bad for you. Why can't spinich be bad for you and ice cream or beer be good for you? I'm going to have to think about this for awhile.