COmtnbabe

Best Honda 400ex Mods

12 posts in this topic

Hi all, I am planing to buy a new 2007 Honda 400ex. I am getting a really good deal on it brand new from a dealer so i want to put a little money in to it. I am just not sure where to start. Any sugestions?

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exhaust, jets, k & n air filter. then if you want more get a 440 big bore kit

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Awsome thanks, any brands better than others? are nerf bars and skidd plates necicary?

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i like nerf bars just for the safety cause my foot has gotten eaten by the tires a couple of times. as for brands i think its personal preference. so i like fmf. ive been happy with everything i use from them

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Best thing to start with is a pipe and intake IMO, remember, most mods require re-jetting. And skid plates are always a good idea.

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Hello everyone!!.....newbee here....

....My son has an '05 EX..it has an Hmf slip-on,Hot Cams Stage I cam,a '04 XR400 head gasket,a '04 XR250 CDI and 'Motoman" high velocity porting...that's about 650.00..

The porting was done by me, so...that was like a freebie..sorta..

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Welcome Bosco

COmtnbabe, I highly recommend a foam filter over the K&N. Especially with how dusty the trails get here. Then add in our frequent water crossings. Skids and nerfs are huge in the mountains too. Curtis Sparks makes an amazing pipe for the 400's.

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Ok Pipe, Jetting, Stage 3 rev limiter, stage 2 cam, maxxis holeshot tires, nerf bars, foam air filter, and an extra oil cooler mod. This is all on my 05 400 and it's pretty awesome If you do bore ht e 400 you will have heating problems to wear you dwon't even wanna put your legs next to the bike. do an extra oil cooler mod if you do bore it. Helps it run cooler and helps keep your engine alive a lot longer.

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Why has no body mentioned anything about suspension yet? i think better shocks (like ones from 450R, or aftermarket) is one of the best mods you can do to something with such crappy stock suspension like the 400ex.

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Well, that really depends on how you ride it. The stock suspension is sufficient for your average trail rider, but for anyone who likes to ride aggressively, I would agree that a supension upgrade is a good call. The rear shock isn't too bad, but the fronts are not all that great. I did away with my stock 250R front shocks because they weren't cutting it, they are much the same if not exactly the same as 400ex shocks. There are some KFX 450 shocks on there now, the aren't as good as a nice set of aftermarket shocks, but they are a heck of an improvement over the stock ones.

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Depending on your money situation, the 450r shocks can be a money pit. If your weight is sufficient, then no need to worry too much, but they usually need to be sent to GT Thunder or someone like that to revalve them because of how stiff they are. But anything IMO is better than the pogo sticks that come stock on the 400EX. I noticed no one mentioned the timing advanced key...boy I ordered on of those and it made my 400 do wheelies through all the gears. Awesome mod! But not recommended with high compression setups. Just my $.02. :biggrin:

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