i was wondering if honda screwed the intake design up on the 400ex like yamaha did on the banshee,warrior,blaster,wolverine and others because my cousin has 99 ex and sand got in his motor and screwed the topend up and honda still covered it under warranty even though he had a K&N filter and outer wear and i also noticed a pro flow intake system for the ex in ad in dirtwheels.

 

In what way is the Blaster's air box screwed up? It is the best of any Yamaha Sport ATV air box design. It always gets 5 stars in air box design by all of the magazines. Have you ever even seen a Blaster air box, it does not rely on the lid to hold the filter in the right spot, it has a cage that the filter goes over and then it is screwed down in the air box with one screw in the middle.

 

Sounds like his filter wasnt on right or has hole somewhere in boot or loose fitting boot.I ride through everything (no lid)and have never had anything get past my K&N w/outerwear.Plus I clean it after every ride.Its nice that they warrantied it though.

 

YEA! What he said! Wait....the Warriors air box does suck!! Fortunatley there was a pro flow on mine when I got it......its great

 

sorry I made a mistake and yes I had a 98 blaster so I have saw a blasters airbox before. jeez I didn't know U would get so wound up over a simple error.

 

I might have the answer. My 400ex filter has came off 2 or 3 times, in the box!! I opened the lid and there was my filter sitting side ways in the box. You can imagine I was pissed. Then it happend again!! To the best of my knowledge it was just sliding off where the clamp goes on. If you don't tighten it on very tight I think it slides off, that lip is not very big. If you tighten it too tight I think it bends the rubber ant slides off also. My friends has never done it though. He says its because I jump too high and the impact jars it loose. But I'm only jumping off a table top jump on to flat ground at about 6 to 10 feet high. The 400 sokes up the jump ok, but it does hit hard. I'm asking every one if its happend to them today.

 

My bro-in-law has a problem with his '99 400EX. We were riding the dunes in CO and it started dying. He took it back to the delaership and come to find out there is sand in the top end and the lower crank was seizing. Every reason they gave him was speculative (it COULD have been a dirty filter, it COULD have been low on oil at one time, etc.).

This bike has been taken care of, ridden little and maintenanced regularly. He now might have an issue with them not wanting to cover it even though he has the extended 3 year warranty. I noticed the 2 posts about the sand in the engine and found them to be a similar type of situation. Even though his filter has never fallen off during riding it did get sand in the engine. Any feedback or information you guys can post and help him with is greatly appreciated.

Thanks,

 

 

 

I run a K&N with no Outerwear yet, I put a healthy amount of grease inside my air box and on the inside rim of the K&N filter to trap sand and dust. Seems to work pretty well so far. I must say that I am not very impressed with Honda's warrenty program.