Problems and value with a 1999 WR400.

I am doing some work on a 1999 WR400 for a friend of mine.  It has been sitting a year and the carburetor is completely gummed up. He wants it running primarily to sell it so he can pay some expenses that have come up.  


  He has removed the carburetor and cleaned it but was unable to start it afterwards.  I reremoved it and found a plugged up pilot jet.  I cleared the jet and attempted to start it.  I have had start briefly 4 or 5 times but never runs longer than a second.   I am probably going to completely remove the carburetor again and this time completely re-clean everything.   Any ideas on what to look for?  I will probably need to get a kit for the carburetor as accelerator pump is now leaking too.  Any electrical problems that could cause this also?


I have to say I have never owned a 4 stroke of this vintage.  Back in 1999 I was still riding 2 strokes as most of us were.  I didnt switch to a 4 stroke until 2005 (Honda).  I am not real familiar with operating a compression release.  Right now my procedure is pull the compression release and rotate the engine around 2 short kicks. Let go of the release lever and give it one solid kick.  Half the time compression stops my kick right in its tracks.  I am wearing boots when I do this as starting with tennis shoes on is not an option. 


During my hour long right leg work out this morning, my knee bumped against the gas tank and hole broke in the side of the tank about the size of my fist.  The tank says clark on it but it does not appear to be larger than stock.  I stuck my old tank from 2006 WR450 on it to continue trying to start it.  No plastics and cant bolt it on but it sits ok in position. 


Finally my final question.  Is once it is all running and cleaned up what is the value realistically for this bike.  It is California Plated street legal with current registration.  We would like to get around 3000 .  I am not sure if that is realistic or not. 


Thanks ahead of time.



You keep saying you cleaned the carb, then you had to remove it and 'clean' it again.............


You have to service the entire carb if you want it to work.

You also have to clear the passage above the pilot, using fishing line and spray cleaner

There is a 90 degree bend up there.



Unless you are doing this, you will continue to have problems:

The Owner of the bike removed and cleaned the carb.  How well he did it I do not know.  I removed the bowl of the carb and cleared some plugged up jets and removed and cleaned the needle and seat.  I am planning to completely remove the carb and clean all of the ports.  Because of the leaking accelerator pump, I will need to buy some parts for it.  Was looking for tips as to what other things to look for.  The tip on cleaning the passage above the pilot is the kind of things I was looking for.  Thank you for that. 

 That passage that Krannie mentions is a real bear to get clean as it makes that little bend from the main throat of the carb down into the well it comes out into. 


On my '03 I had to take a real small piece of wire and  sand the edges so it would not scar up the passage and had to sort of poke it out a little at a time after I let it sit with gas in it one winter.


 It is real hard to spot too as it is a tiny hole. Look for it about in the middle of where the slide sits on the bottom side of the main throat of the carb.


 I have never had to clean out the one on my '99, it is a slightly different carb than my '03. I know until I cleaned that out on the '03 it was real hard to start and did not like having the throttle snapped open.


 The compression release is more of a tool to help you position the crankshaft to a point where you can spin it over once only. IF all is good, that is all it will take to fire it up.


 Starting procedure on it is as follows.


First time of the day I like to first pull in the compression release and kick the motor through 2-3 times with the enricher (choke) button pulled out.


Then release the compression release and kick the motor over slowly till it stops due to hitting the next compression stroke,


 Pull the compression release in again and kick down maybe 70-90 degrees more, just about 1/4 of a revolution more on the kick starter.


 Let go of the compression release, allow the kick starter to return to the top to be able to get a full kick, and then kick it like you REALLY want it to start.


 The rest of the day (after the bike is warm) you just kick it over till it hits compression, use the compression release to get it just past TDC, and then kick it like you REALLY want it to start.


 Usually mine is a one kick start no matter if hot or cold....unless we have been taking a soil sample, then sometimes it can take 3-5 kicks, which is what really wears me out over the course of a day!


 Tanks get brittle with age. ESPECIALLY if allowed to sit over winters with old gas in them. I have split a couple with just slight bumps so now try to drain them over winter if not used regularly.     

The only way to clean a carb is to get a paint can size can of 'carb boil-out' and soak it for 4 hours or so

To mechanically go in there and get a wire or something and think you have found every one of those passages is futile

The only way to clean a carb is to get a paint can size can of 'carb boil-out' and soak it for 4 hours or so

To mechanically go in there and get a wire or something and think you have found every one of those passages is futile

 Baloney....A.K.A. BS!


 There are not that many passageways on one of these bike carbs. ALL of them can be cleaned out manually using care to not scratch them up. They were put in there mechanically using drills and reamers, although on some they close off or cap off some of the access ports they used to machine in the holes and passageways.


 The carb manufacturers are working on building them with as little machining as possible as it saves time and manufacturing costs, but lots of the passages are STILL machined out to get the tolerances and finishes right.  


You want to see a lot of passageways go down to a local tranny shop and view a valve body for transmission, or better yet look at a valve body for a BIG dirt a Euclid Truck!


 When I was just a pup I worked for Southwest Kenworth and we also had the contract for some of the mine equipment here in the Southwest. I was always fascinated by the almost clean room conditions they had in our shop to clean out those valve bodies for the earth moving equipment. Some of those had over 200 passageways and ALL had to be clean for the automatic transmissions to operate correctly ....... Know how they cleaned em out? Pipe cleaners, wire, compressed air, and q-tips! They would find where one went by squirting in WD-40 and watch where it came out so they could clean them from both ends. They did use carb cleaner as well but all were swabbed out to ensure they were absolutely clean.


 As for carb cleaner is it not near as potent as it used to be. It has been diluted down so bad compared to what it used to be that now-a-days it does take four hours of soaking time to clean things out, and that is just on a mildly gunked up carb. Course you can thank idiots that do not use gloves or safety glasses, plus the nanny state for that. 


 If a carb has sat for long, especially with old gas, even soaking them will not clean out some of the tinier passageways, that is where a bread tie stripped of plastic or paper, or sometimes the SHANK end of a number drill, (NOT the drill end, as it could scratch the hole or passage)  can be used to convince the "plug" to push out.


 On the hole in question here I had to look long and hard to find a small enough wire to fit into it as it is pretty darn small. I took great care with some 400 and then 600 sandpaper to be certain I had worked the cut off edges of the wire down all around so it will not scrape or cut into the body of the carb as that hole does make a turn so the wire  has to slide on the casting some In order to make it down into the fuel well when being pushed down from inside the carb throat. 

Never ever ever soak an FCR carb in anything but Simple Green or other non-solvent.  Maybe Pinesol for a few hours and then rinse with alcohol.......


If you soak it in solvent the main seal will dissolve and make the carb usesless.....


These carbs are super simple to clean.


...but pulling off the float bowl cover and playing with the jets is only about 1/5 of the job.


You MUST dismantle the entire carb (but do not split the body) and chase out all the corrosion, or it will come back...........


...and you have to replace the wear items while you are in there: needle jet, slide plate and seal, needle valve, apump diaphragm.

Good luck getting $3000. I paid $3500 for a 2003 WR450, plated, with unused factory wheels/tires and a NICE set of Excel/Talon 17s with a Brembo radial master and Braking 4pot caliper. I imagine the magic button and extra power of mine means it's worth more stock, too.

Good luck getting $3000. I paid $3500 for a 2003 WR450, plated, with unused factory wheels/tires and a NICE set of Excel/Talon 17s with a Brembo radial master and Braking 4pot caliper. I imagine the magic button and extra power of mine means it's worth more stock, too.

I agree, I paid $2000 for my 03 WR450 in near excellent condition. After the Tusk street legal kit I will still be under $2200 in a street legal WR. $3000 is a stretch for that bike but, it all comes down to how much the buyer is willing to spend and how bad he wants the bike.

From what it sounds like the bike is probably worth $2000 at most IF it is running good and looks halfway decent. The thing that you got going for you is it is CA plated. You can tack on another $500 for that.

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