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Uncorking problem


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So I got all the EPA crap off, new main jet, needle, pilot jet, manifold, filter and muffler. Got it all back together and it fired right up but if I give it over a sligh twist of throttle it dies. The new needle is set at 3 from the top...what gives? Did I screw up something in the carb?

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Got to www.partsfish.com and sign up for a free account. They've got the XR650R microfiche with the exploded parts breakdown online to view. It's quick to do and once you pick the XR650R to view, just select the carburetor parts diagram to view and it will have some pictures to help you out. As they say, a picture is worth 1,000 words.

Did you also remove the two airbox restrictors? I didn't see that in the list you mentioned which is I'm asking. You may also need to adjust the pilot/fuel screw, but that's no biggie. Does it die when opening the throttle just a little bit or just when you whack it open?

Before adjusting the pilot/fuel screw, make a note of where yours is adjusted. Turn it in all the way and count the turns in until it stops (do it gently), but be careful when it stops and don't crank it tight because you can easily damage the seat. Then put it back to where it was. To adjust the pilot/fuel screw, first make sure sure your engine is fully warmed up and set the pilot screw to 1.5 turns out. Then turn the pilot screw clockwise until the idle slows. Then turn the pilot screw counterclockwise until the idle slows again. Make a mental note of how many turns you made in between the low idle points. Then turn the pilot screw half way between the low idle points to finish the adjustment. If you turn the adjuster counterclockwise and the idle doesn't drop down, then you need a larger pilot jet. If you turn the pilot screw clockwise and the idle doesn't drop down, then you need a smaller pilot jet. After adjusting your pilot circuit, re-adjust your idle speed if necessary. Again, don't crank down on the pilot screw when it closes or you'll damage the seat, so be gentle when it stops or becomes harder to turn.

Don't fret yet cause it's probably something simple. We've all been there at some point. ?

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ok so I was reading the manual and it says to install the needle jet with the smaller diameter into the body...is that the ID or OD of the needle jet...thats the only thing I think I could have messed up. I put the larger ID on the upper side (pointing up). Im upset that I messed something up and trying to figure it out on my own...

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The requirement for jet sizes and carb setup will vary depending on the temperature, altitude & humidity you're riding at in addition to any modifications on a given bike. There's no one size fits all here and most advice given gets you to a starting point that suits many just fine. Many people never go beyond that, but getting a bike jetted for optimum performance for a specific riding location in addition to the specific modifictions takes a good bit of time, patience, knowledge, plus some trial & error. Dyno tuning is helpful, but even that doesn't tell the whole story, especially at part throttle opening and it doesn't take into accout the various loads you'll encounter, etc. Unfortunately, the seat of the pants meter still has plenty of merit ?

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ok I think I am stupid...does the needle go above the slide or insert needle then put in slide? I put the needle in and then the slide on top...I took a double take becuase it looked really wrong and that the clip did nothing but I recalled thats how it came off...looking at schematics it appears that the needle goes in after the slide goes in...DAM IT. So I am gonna pull it apart, check the needle for damage which I am sure it is damaged since when I assembled the carb I cracked the throttle several times to check the cables. then put the slide in and then the needle...never enough time to do it roght the first time but always enough time to go back and fix it.

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so I was reading the manual and it says to install the needle jet with the smaller diameter into the body

Oh, I thought you were talkng about the needle itself earier and not where it seats in the jet. What I told you in the other post was in regards to the needle itself where I said the tapered end points down and the top part of the needle with the clip on it faces upward.

Are you wondering about the jet the needle seats into or the needle itself?

In regards to where the needle seats into the jet, the side that should be facing the top should have a wider opening than the side facing the bottom.

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does the needle go above the slide or insert needle then put in slide? I put the needle in and then the slide on top...

Yes, the needle goes 'down' through the top of the slide and the clip position is what determines how far down the needle sits. The higher the clip position, the lower the needle sits and the leaner the mid range will be. The lower the clip position, the higher the needle sits and the richer your mid range will be.

Your needle 'might' be OK, so don't worry too much. If worse comes to worse, just put back the stock needle and use it on the 4th clip position for now. Many people use the stock needle with excellent results and run their bikes as is and are as happy as a clam.

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Your needle 'might' be OK, so don't worry too much. If worse comes to worse, just put back the stock needle and use it on the 4th clip position for now. Many people use the stock needle with excellent results and run their bikes as is and are as happy as a clam.

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I don't recall 100% for certain if there was a difference or not between those two seats, but I kind of recall them as being the same. It's been a long time, but I do recall the needles being different, but not the seats. My guess would be the seats are the same.

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