Howdy this is my first post here. I bought a 400ex last year for my wife, and I just bought one for myself. Hers is a 2003 and mine is a 2004. For some reason mine seems to be a little faster then hers? Have they changed something? I have done a ton of searching on what mods to do. We mainly ride in the dunes near our town. I dont wanna sacrifice reliability at all cause I dont have the money to rebuild them all the time. The only thing I have done is gone one tooth down on the front sprocket and added a set of paddle tires. It sounds like to get me started I need to buy some sort of high flow air filter, add a bigger Jet in the carb, and a slip on pipe. Anyway what are some budget minded suggestions for those things? Also your favorite place to buy them? If it matters I love to trail ride in the sand, I am still learning how to jump and hill climb. I normally wipe out when I get alot of air, gotta figure out how to do that better I guess....[img]i/expressions/face-icon-small-smile.gif[/img]

 

i think the carb is bigger on the 04 get a hmf slip on or a white bros e2 slip on and k a n filter

 

Was your 400ex faster before you changed the sprocket size? I agree that Honda did make the carb bigger for 2004. How much of a difference is there in speed?

I would probably leave it stock but I'm used to having a top speed of 52 mph. I guess most people begin with things like jetting, exhaust pipe, air filter and a sprocket change.

One item could be cheaper at a atv parts site and more expensive at the next. It's good to shop around.

 

If I were you I'd go with a Uniflo air filter, no airbox lid and a slip on muffler. Use proper jetting too. You can get the parts you need at World Honda there in Coos Bay or order online. I have found Rockymountainatv.com to be a great place to order parts. They will also send you a catalog twice a year. Items are usually less expensive online. Compare price though and add shipping costs to the price of online purchased items. You are lucky to live so close to the dunes, I am envious. It is an 8 hour trip for me to Coos Bay dunes.
Practice your jumping at the hill next to the top of box car. Not too big of a lip with a smooth landing area. Also other good small jumoing lips in same area. Great place to practice. Lots of fun trails all up and down Bull Run.
When you are practicing your jumps make sure to hit the lip square on so as not to launch yourself sideways. You can correct a lot in the air just buy steering the way you want to land. Even though you are in the air this will change the angle of the bike. Start off slow and before you know it you will be hitting the lips in 4th gear pegged.
Good luck and have fun! Get a set of paddles if you haven't already. I have Sand Sharks and Kenda Geckos. Angled paddles are great if you love to rip through the dunes and trails. Straight paddles are great for sand drags and hill climb racing.

 

Congrats on your new quad. You can do alot of mods without sacrificing reliability, the EX has been out long enough to where most people have figured out what works and what doesnt. I'd say if your only ridin in the sand get a k&n filter and remove your airbox. You will need to rejet but should be very easy. I'd do a complete pipe, not just a slip on. Yoshi makes nice pipes that arent too loud. Call some local builders and seee what they recommend. There are two in Salem that I like, MacRacing and DTR. Both know their stuff and are willing to help. Also check out other forums Like EXRIDERS, NWQUADRIDERS,SANDLAKEDUNERS,etc. Most duners are willing to share their know how. GOOD LUCK

 

Cool, thanks alot for the help! I really appreciate it. I bought some sand geckos when I purchased the quad. Also my 04 was def. faster then my 03 both before and after the sprocket change. I actually havent got to ride it since we changed the sprocket, but my wife said it is harder to keep the front end down. She said she could pull a 4th gear wheelie very easy.[img]i/expressions/face-icon-small-smile.gif[/img]

 

A smaller sprocket on front will reduce your top end a little but will also make it a little quicker as it will wind out in first faster. What are your favorite areas in the Coos riding area? I haven't been down there since last summer so I was riding my 400ex which I gave to my son when I got my 450R. We when to Florence this past April with my 450R and I love it. The only thing I didn't like about Coos was the 3 mile long whoops trail to the beach and between the north and south riding areas. Bull Run is a lot of fun! We stay at Horsfall Campground. Need to get down there again soon. We should hook up if I make it down there anytime soon. Always great to meet other riders.

 

Yeah that long whoop road sucks! My favorite areas are between box car and hauser. I have always been into Jeeps and stuff, It's funny I am totally comfortable jumping my Jeep out on the dunes but I get a little nervous on quads. If you go out towards horsefall beach there is a smallish looking dunes access area about 1/4 mile from the borsefall beach parking lot. It goes out to a big bowl and you can follow that across trails and smaller dunes and come out on bull run road or hauser. Thats a pretty fun road to. Yeah that'd be cool just post it up when your coming down!

 

the 400ex has many many aftermarket items to choose from. a good start would be to get a slip on pipe or a full system then get a aftermarket air filter, uni is good and i think k&n is alittle over rated. Also run without an airbox lid and maby get some outerwear for the air filter, dont really need it but helps keep sand particals out. then make sure you have the right jet in it. after those modificatoins you should be happy.

oh yea and about the front sproket size maby you should go back to stock, it might be faster. then after you do some mods go back with the one u had. just a sujestion.