WR400 Questions

Ok guys, this is my first post on TT but i've been lurking for a good few months, a few weeks ago i bought myself a WR400 for the bargin sum of £1400, it's still in need of a little tlc but is kitted out with Renthal Fat bars, White Bros E-Series exhaust, carbon skid plate, a few other little bits and i just bought a new set of Braking wavey discs for it aswell as EBC pads.

However on this beastie the plastics are a little dull aswell is the exhaust is a little dented and a tad too loud for my tastes, i rwally want to update it a bit because it's absolutely ace offroad! I know alot of 426 parts and even 450 parts fit onto this bike but would like to know what i need to do to get 450 plastics to fit aswell as if a 450 exhaust would fit my bike? Plus any other little tips and tricks you know (i do know about the free mods tho)



I doubt the exhaust from another model will fit. The 426 got the alum subfram and changed the mounting. Something might fit but I doubt it. The WB E-series pipe is LOUD. Nothing you can do about it other than get something else.

Pull the bike down and grease anything that moves or has bearings. Check the valves and stay up on maint and you'll have a good bike for a long time to come.

As far as a pipe, the 426 pipes will fit, 450's won't. I have a stock YZ pipe on my WR (cheap, lots lighter than stock, and flows better) with a pro moto billet spark arrestor end cap and quiet insert. It consistantly passes 96 db sound checks.

As far as 450 plastics, there are several threads here on TT about doing the swap. Basically, you need the 03-05 subframe, airbox, tank, shrouds, and side panels, and you hae to make a bracket to raise the tank mount pick up point.

I am pretty sure there is a post on here somewhere else about the 450 pipe on a 400, from memory as long as you get the earlier 450 pipe off the steel frame versions, 03-05 ? the pipe will almost fit, there is a slight difference in the middle mount which just needs to be " reamed" out slightly so the bolt will fit. There is definately posts on putting the 450 plastics on, it looks great but there is a fair bit of work involved, the air box and rear frame need to be swapped to do it properly and mounts need to be made to fit the tank, there are some good pics of a YZ that was upgraded if you do some searches thru the old posts you will find it. An easier swap is to put a YZ 400/426 tank, seat and radiator shrouds on your WR 400, especially if it is the big tank version of WR.

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