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superbiker

2004 WR450 Carb Please help!!

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Hello, I have a 2004 WR450.

I was having a issue with the carb over flowing. I checked the needle valve and seat in the carb and found the neddle is grooved. So i went to my local dealer to get a new neddle and seat. The dealer told me that only the needle is avail. from Yamaha , weird normally when you replace the needle you do the seat at the same time. well any way i went ahead and replaced the needle 31dollar part hoping the seat is good and its only the needle. Well i have replaced the needle and still the carb overflows. i have double checked the float height to make sure that is not the issue.(not the issue) What do i do now buy the 900dollar factory carb the 600dollar sudco carb??? all for a simple 20dollar brass seat..has any one had this issues? what have you done??

thanks

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I have the same bike with I think the same problem. Cuts out in whoops, or similar conditions. When terrain smoothes out, recovers in a second or two. It is fresh back from the dealer too who supposedly went through the carb completely, but I am suspicious. I heard high float level too. If that's okay, I heard that the float can soak up liquid and become too heavy raising the fuel level in the bowl. One guy said he determined this was the problem by weighing a new float and the old. I've never seen our float, so I'm not sure if ours are porous, or metal like some I've seen. I may suspect wiring as some people suggest if the condition IMMEDIATELY is cured when the terrain becomes smooth again, but mine chokes for a while even after smooth terrain returns, so I think carb. I need to fight with the dealer since I paid them to fix the carb. I'll let you know what happens...

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The seat is replaceable. Call Carb Parts warehouse.

Floats can go bad and sink. Rare these days though. Used to happen when they were made of brass and would develop pinholes.

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The seat is replaceable. Call Carb Parts warehouse.

Floats can go bad and sink. Rare these days though. Used to happen when they were made of brass and would develop pinholes.

The seat is pressed into the body of the carb, unlike the earlier FCR which held the seat in place with the flanged portion of a retaining bolt. I don't see how you would remove it without some kind of specialized tool? Any ideas? Also, Yamaha (and Sudco ) sell the valve seat assembly for the earlier FCR, but don't seem to carry the seat for the later model carbs.

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On my '02 WR 426 I had the same problem developing. I found the o-ring that the seat used for sealing the inlet fuel from the bowl had gone bad and was leaking fuel past the outside of the seat and bypassing the needle all together. The seat on my 426 was removable , but it looks like they did away with that on your model year, at least in the manual. I'm with SXP, I don't see that as being the problem, but I would still check that the pressed in seat is tight in the bore. Follow the path of the fuel through the carb and you should find the problem. :cool: WR Dave

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On my '02 WR 426 I had the same problem developing. I found the o-ring that the seat used for sealing the inlet fuel from the bowl had gone bad and was leaking fuel past the outside of the seat and bypassing the needle all together. The seat on my 426 was removable , but it looks like they did away with that on your model year, at least in the manual. I'm with SXP, I don't see that as being the problem, but I would still check that the pressed in seat is tight in the bore. Follow the path of the fuel through the carb and you should find the problem. :cool: WR Dave

so its starting to look like im screwed... and have to replace the whole carb.

what a dumb ass design why would they not have a replacement for the seat? when the needle starts to groove chances are the seat grooves as well.

any one know what carb to buy from carbparts??model number? will i have to rejet or will it come as a straight bolt-on?

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check first that the hot start cable isn,t tight around the frame especially if you have changed bars?.I hear that next years yamaha has a special part to replace the brake pads,It's called part number ( BIKE ASSY, ). I went in to get a new seal for the speedo drive and was told i had to get a speedo drive assy, walked straight out.I would like to see a topic on this site stating 1 - make. 2 - model .3- common replaced items and cost to repair,replace.Bikes cost enough with out having to replace hole assy,s instead of repairing with minor parts.

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Before you give up on it, remove the carb and and rig up a jug of fuel with a small hose to the carb inlet fitting. Then remove the bowl and hold the float closed to see where the fuel is coming from. If the seat is damaged , you may be able to take it to a machinist to clean up the surface. Just some ideas to help save you buying a new carb. WR Dave.

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I agree with WR Dave. I would verify that the seat is bad and that it can not be fixed before spending the money to buy a new carb. My $.02

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Seat is bad...

yamaha carb 5TJ-14101-50-00 RTL$900 ouch..

any one have the part# for the FCR from some one like carbparts. or Sudco? ?? Thanks for everyones help I tryed all suggestions. but in the end i knew i was screwed..

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Before you give up hope, give Zip-Ty Racing and/or Tokyo Mods a call. They do magic with FCR's and may be able to help you. Also, if you haven't done it yet, post your problem on the jetting forum. Eddie the moderator is a carb guru and may have another solution. If any of my suggestions work out, you can just send me 10% of the amount you saved :cool:...SC

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thanks Clark,

I will try to contact carbparts and see if i can order one with the o-ring..

hopfully it will work.

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you would think they would make it out of a hard material if its not replaceable .

at 900$ i would go to a aftermarket or older carb . why buy the same stupid thing .

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