Hi everyone. I am new to this forum. I bought a 2004 trx400ex left over about 3 months ago. I bought a K&N filter and have run the bike with and without the lid. I did some research looking for people's opinons about aftermarket airfilters and I am a little worried. Many people are hating on the K&N saying that they don't provide the protection of a foam filter. I ride mostly on trails and it is real muddy in some areas and real dusty in others. Should I go with the UNI and consider the $60.00 spent a lesson?

 

Yes. Consider it an expensive lesson. I use K&N's briefly. When I changed them I would wipe out the intake boot with a white cloth to see of I was passing dirt. There was always a light film of dirt on it. The performance gain is not worth the risk. Leave the K&N's for street use only.

The system I settled on is a ProDesign adapter with foam filter (made by UNI) and an EHS Racing airbox lid. This gives a nice balance between performance and protection!

 

I apologize for not saying thank you for your response, I thought I had replied. I ended up getting a Twin Air outer filter using the stock inner filter. What type of inner filter do you reccomend to replace the stock one? Thank you again for response you saved me from probably ruining my new bike

 

i have 99ex been running a k&n on it since new never had a problem.

 

Do you have an outer filter or screen that covers the K&N? I was really concerned because I ride in such muddy and dusty trails.

 

I was curious about that too. I want to get a power adder kit but not sure which one is the best. Involving the air filter that is....

 

i havent had 1 but i would recomend it.

 

Thanks for the advice