Which carb path to follow for 99 WR400?

This girl is tough to start all right....don't even mention if she is on her side for a minute or so! It is in great condition otherwise...plated in CA :confused: Before I decide to take it to the shop and drop at least $200 to have them check the carb and clean it out...would another more modern carb that you could more easily adjust for altitude be a better avenue even it costs twice as much?

The JD jet kit and shop fees would probably already run about $300:banghead:

If I went with a new carb...what would the original one sell for if it is in good condition...just needing cleaning?

Thanks so much for the help.:thumbsup:

Your options aren't many for a "more modern" carb. Maybe a gen-2 FCR from a 426 or 450. You could also go Edelbrock, but the reviews in the past in this forum reflect great performance when new, but a real finickyness when a bit worn (and that they wear quickly).

You might try a couple of things on your own...first, cleaning a carb and changing jets is easy...save some bucks and do it yourself! The manual tells you how. Are you sure you have the stareting drill down? Normally, once you have the drill down, these bikes aren't that hard to start. Third, try a new plug. When my 426 gets a bit stubborn, that usually does the trick. While you are swapping the plug (and have the tank off), you may want to run a quick compression check. The bike is a bit older, and worn rings will make it hard to start (does it smoke or burn any oil?)what condition are the valves in? I realize it's a 400 and the SS valves don't wear like the Ti ones do, but really hard starting can be a sign that the valves are hanging open a bit. All this stuff is easy for the backyard mechanic to do with very minimal tools. Once you've checked the obvious, then it may be time to play with jetting a bit. Another thing...are you sure the hot start hoses aren't cracked and checked, and that the hot start is working?

I ran an Edelbrock on an '00 WR400 for 3 years. The Eddy did not deliver the top end that the stock FCR provided, but the power was perfect for trailriding, linear power curve with plenty of low-end grunt, much improved fuel mileage and absolutely no jetting hassels. Yes, the Eddy did finally wear out, but only after using it on two stock XR600s, an HRC 628 and finally modifying it to work on the WR. I definitely got my money's worth.

I have been running an Edelbrock on my 400 for the past four years after getting tired of working on the stock FCR. Totally pleased with it. Not sure what there is to "wear out" on the Edelbrock, they're so simple. A few months ago I replaced the needle and seat and gave it a good cleaning just for good luck. I think it is a great improvement to the bike and a simple turn of a thumb screw can fine tune the jetting for different riding conditions, although it is not very sensitive to altitude in my experience.

Before you replace the carb I would replace the exhaust cam with an auto-decompression one. I was ready to sell my WR because it was so exhausting to start. The decomp cam made it so much easier to start.

Is it hard to start cold , hot or just all of the time?

Hard to start most of the time....I will try and clean the carb, put on an autodecompression exhaust cam and a new timing chain....hope the works! Joe

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