Long time reader desperately needs advice!

Hi there! long time reader of your excellent forum , my first post is asking for help!

On sunday (98 WR 400) my bike just suddenly started to struggle and splutter / backfire like it was short of fuel, after just about making it home i cleaned all the jets check needle etc and got quite allot of gunk out. the bike now starts and idles but just splutters and stalls when you hit the throttle. So i looked at that little nipple that squirts the fuel... its not squirting! it used to becasue if had an eye full of petrol before.

the pump is good but the head of the jet looks worn, iv i put a srynge to the feeder and i can get a very small amount of liquid to come through if i really force it. but no long fine jet.

Is this replaceable (i cant work out how)...please help i cant afford a new carb!





Have you tried taking the diaphram out and blowing it back through,from where it sqirts out, with an air line.Watch out for anything that could get blown away or damaged while your doing it too.I am not an expert, it's just a suggestion.Good luck.

You've got a piece of crap in your AP nozzle, and probably in some of the other passageways. Give the whole thing a good douching with carb cleaner, soak it if you must, and blow it out with an air compressor. Lather, rinse, repeat until it squirts again. DO NOT put anything through the small hole in the nozzle or you'll being saving your pennies for a new carb. Reaming out that hole is a BAD thing...SC

it looks quite worn (battered) and has play in it , can move it up and down about 1mm. does it come out?



Time to dump that old FCR and replace it with an Edelbrock carb. Did that on my 89' WR and it is so much easier to jet (no jets). My FCR got so bad with corrosion in the passages that I could not get it cleaned out enough to run properly. The Edlelbrock is awesome, no flat spots, easy starting, perfect carburation at all throttle openings. About 1/3 the cost of an FCR.

An '89 WR400, huh? What's that look like? :thumbsup:...SC

An '89 WR400, huh? What's that look like? :thumbsup:...SC

I think he's off by a decade :thumbsup:

An '89 WR400, huh? What's that look like? :thumbsup:...SC

:thumbsup: An old TT with new WR stickers!

You guys are heartless! Sorry about the transposition. 98' WR Yamaha did make a WR in 89' but it was a 250 two stroke.

What can I say, I'm a stickler for accuracy...spelling and penmanship counts as well :thumbsup:...SC

Then you should know that the correct phrase would be: "...spelling and penmanship count as well.." :thumbsup:

So if my AP Jet is is naffed the only solution is a new carb?

You've got a piece of crap

I second that :thumbsup:

So if my AP Jet is is naffed the only solution is a new carb?

No man.

1. Dissasemble the whole carby. You really need a manual to feel comfortable about that. take out all the jets. Break that thing down ALL the way. Free manual for you.


1b. remember how that slide cutout goes in, everyone puts it back together upside down. The second you say, I wont do it, you will.

2. Soak everything in carb cleaner for a week (We have Chem Dry and Berrymens here) I think Grayracer has a good formula for cleaning solutions too, like a mix of kerosene and ATF.

3. Buy a couple of cans of Carb cleaner spray. Spray out EVERY passage you can put that nozzle in.

4. Finally, blow it out with compressed air.

Put it back together and you should be fine.

ps, don't let your bike sit around with old gas. If you must use some Stabil or some other gas stabilizer. You let the gas varnish and gunk up your carby.

pps, make sure your air filter and boot is surgically clean and properly oiled.

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