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Best performance Changes for 400ex
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Posted by: Quaddog3

Ive been serching the threads but all upgrades refer to 440's 450's 416's etc.

What would be a good mod on a std 400ex for better acceleration.
It already has a WB Eseries exhaust and an over rev. but I need to get out of the gate a little quicker.

Cheers n beers.

Posted by: Wheelie

K&N Filter, remove airbox lid and choke, and rejet.

Dropping one tooth on the front sprocket is also a popular mod.

Posted by: Quaddog3

Many thanks.

Posted by: <DRS>GPF

if your really looking to squeeze out all you can with stock, you can grind down the weld seam on the inside of the headpipe..

Posted by: ride hard man

quote:
Originally posted by Wheelie
Dropping one tooth on the front sprocket is also a popular mod.

This mod helped me out a ton on bottom end.

Posted by: 400exstud

A 450R motor

Posted by: swva400ex

cam

Posted by: AR15 guy

Basically any mod that will add power to a 416, 426, 440, 460 ect will also make more power on a standard 400ex.

Posted by: ohsobad_chevy

quote:
Originally posted by 400exstud
A 450R motor

Anyone else hate smart aass comments like this??

Posted by: PismoLocal

quote:
Originally posted by ohsobad_chevy
Anyone else hate smart aass comments like this??

yep

Posted by: swva400ex

i second

Posted by: 400exstud

It is infact true.

You can find a slightly used 450R motor on ebay, sell your 400ex motor, and only be out a few hundred bucks. This alone wil give you as much if not more than a piped, big bore, cammed, bla bla blaed 400ex motor, with more reliability, and with more potential.

It has already been done to numerous bikes and is proving to be worth while to those that have dumped loads of cash into their 400ex chassis and just can't afford to part with it.

Posted by: Quaddog3

A mate has a 440 kit so will probably go that route and drop a tooth if needed, also K&N and take off the lid.

Thanks for the help, inc the 450 comment

Posted by: 400exstud

For your viewing pleasure

http://www.exriders.com/vbb/showthr...threadid=227736

Posted by: ELewandowski

I would go with the new front sprocket. Makes a huge difference on a stock 400ex. And its cheap.