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XR650R Carb Problem


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I am switching back to the stock carb, to try it, after running the Edlebrock. The bike came with the Edlebrock installed. I put the proper jets in the stock carb, 175 main, 68s pilot, and the comp needle in the middle position. I've just installed the stock carb back into the bike and have some issues.

It seems difficult to start. And when it does it usually revs high then shuts off. Doesn't seem to want to keep running. It did a couple times though but I haven't really been able to repeat that.

Any ideas on where to look?

Thanks,

Brian

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You've got the right jets but you need to put the needle clip in the 5th groove from the top. Turn the fuel screw 2 turn out from seated and set your floats at .62in (16mm). Check for air leaks also. Double check the vacuum port on the intake and make sure it's plugged. I don't blame you for tossing the 'Brock, I hate those f@#&%ng things.

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What elevation are you at? That's more of a sea level setting IMO,although you sound lean,, I ran a 165-168 main 3rd clip down and a 68s pilot.With a full pipe system etc.,when i ran the stock carb...

At 3000 to 8000 ft.

Iv'e heard the edels can be a pain and i can see some flaws in the design,but so far i still love mine.

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You've got the right jets but you need to put the needle clip in the 5th groove from the top. Turn the fuel screw 2 turn out from seated and set your floats at .62in (16mm). Check for air leaks also. Double check the vacuum port on the intake and make sure it's plugged. I don't blame you for tossing the 'Brock, I hate those f@#&%ng things.

Can you explain to us a bit more about the vacuum port, im not sure what port your talking about and why does it need to be plugged?

Where abouts is this port, whats it look like, what does it do etc?

cheers.

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Can you explain to us a bit more about the vacuum port, im not sure what port your talking about and why does it need to be plugged?

Where abouts is this port, whats it look like, what does it do etc?

cheers.

He might be refering to the 'idle down enrichner diaphram'?(On the side of the carb).Some people block this off.Or it might be an 'OZ bike' thing.?

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Not to thread jack, but why did you toss the Edelbrock? I've got one on my 650l and I'm concerned that I'm only getting about 30mpg. Are these carbs crap, or does it just need to be dialed.

I'm new to these bikes so I'm looking for feedback from those in the know.👍

Thanks

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Can you explain to us a bit more about the vacuum port, im not sure what port your talking about and why does it need to be plugged?

Where abouts is this port, whats it look like, what does it do etc?

cheers.

there's a vacuum connection on the engine side of the carb that needs to be connected to the air cut-off valve(ACV)...

...sounds like u've got a "lean surge"...i wud check the fuel flow(restriction), bowl level(low) or for a tiny speck of dirt in the pilot jet(hold it up to light to inspect)...

my SWAG is sumtin restricting the pilots fuel flow (dirt)🤣

👍

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Can you explain to us a bit more about the vacuum port, im not sure what port your talking about and why does it need to be plugged?

Where abouts is this port, whats it look like, what does it do etc?

cheers.

Just past the carb insolator on the top left side of the head there's a vacuum port that's drilled through to the intake port. It is part of the Pulse Secondary Air Supply System and a vacuum hose ran from the port on the head to the pulse secondary air injection control valve. The valve would pump pulses of fresh air into the exhaust ports so as to lower the hydrocarbon emissions going out the tail pipe. Most XRRs have had a "smog block-off" kit installed so the valve and all the plumbing is gone. However, there are several ways that the vacuum port on the intake can be plugged. Some times the nipple is removed and the hole is plugged with a screw, this is the best way. What I've also seen is a rubber cap on the nipple, these tend to dry and crack with age and that makes a monster vacuum leak and overly lean combustion. BTW this smog equipment is only found on California models and all '06 and '07 XRs.

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Not to thread jack, but why did you toss the Edelbrock? I've got one on my 650l and I'm concerned that I'm only getting about 30mpg. Are these carbs crap, or does it just need to be dialed.

I'm new to these bikes so I'm looking for feedback from those in the know.👍

Thanks

Use the search tool on the top of the page.There are all kinds of opinions\facts on this carb.
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