A change


Just thought I'd do an intro!

I've just bought a WR 400 (2000), What a £$&*£$ animal of a bike, maybe I should sell my Gixxer 750 and supermoto another WR?

Unfortunately I spilt it down the road after only owning it 2 days, I guess riding on the road on crosser tires wasn't the best idea, I hit a patch of diesel and the thing just folded. Thankfully both myself and the bike survived with minor injuries.

I don't really know to much about these bikes so I guess from time to time you may get some dumb ass questions from me! :cry:

One thing which is bugging me is this back firing and stalling when i give it a fist full, having read a similar post on the forum I guess it needs re jetting? (competition can fitted)

Catch ya later folks!

The Ferret :cry:


Wicked first post.

Hello and welcome....glad you like the bike, mine backfires a tad too, think its to do with the over run....sounds good though dunnit.....twins and singles tend to do that a fair bit.

If its stalling then maybe you should get it looked at, sure some tech chimps will be along in a moment.

Good to have another UK WR rider here though!



When you nail the gas of idle it has a bad bog and it will stall. There is very little you can do about this. The only thing is to get a new bike. As for the backfireing, it is normal. It will bacfire a lil on deacceleration. But if it backfires hard then it is a jetting problem.

I can't imagine needing to change the bike for a small fueling problem such as this! :cry:

I've had it looked at by a mate who's a spanner, he thinks the carb just needs stripping down and cleaning and maybe re jetting? He's gonna do it this saturday, I'll let ya know if it's cured!


It won't be. I'm telling you you cannot wack it open. You have to roll past idle then wack it open. Well increase your idle if your so worried about it.

I don't have any experience with the "bog" issue, but from what I have read, Yamaha fixed this on the newer models with a "leak jet."

There is a company called Dial-a-Jet that makes adjustable "leak jets" that you install in your air boot that let you go to different altitudes and temperatures and whatnot, and all you have to do is turn a knob to richen or lean the whole throttle range, it supposedly fills in "dead spots" too.

I would think that this MIGHT cure the bog problem on the older bikes. :cry:

Had the carb stripped, hasn't cured the 'bog' issue although it isn't as bad, feels more 'crisp'. Also had the back jacked up a little, to much sag before, steers a little quicker now!

Still waiting for my new M2R 'Bradshaw rep lid to arrive and my Renthals, treated myself to some new Oakley enduro O frames too......spoit $#%&*%#

I have 98 yzf 400 setup for flattrack. I love it!!!! You may have an exhaust leak that will make it back fire on deacceleration. My bike is pretty responsive off idle. May need to adjust fuel screw. Thats my two cents

try the "P38" accelerater pump cover thing, it is supposed to reduce bogging when you first whack open the throttle. try imotoracing.com for fidning the "P38".

good luck

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now