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Vacuum fuel pump on 675cc bore

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3 minutes ago, baldy110 said:

Yeah so what so does mine and I'm running the stock carb with a 155 main jet and it runs great.  

what piston are you running and what tank do you have ?

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2 minutes ago, whiteXR1 said:

 

i have full exhaust , K&N filter and the jetting is almost max out for the OEM carb and  my plug looks a little too clean for  top end 

Again so what so does mine and again the OEM carb works just fine.  Why come on here and ask for advice when you won't take it?  If you already know the answer then why ask the question.

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5 minutes ago, whiteXR1 said:

what piston are you running and what tank do you have ?

Wiseco 102mm, 10.5-1 compression, cyclewizard #10 camshaft, ported head, big valves, big fin head, full FMF exhaust, Uni air filter, oil cooler, intake mods, Clarke 4.7 tank with OEM petcock. Have no idea why you think the gas tank is an issue.  It doesng matter what the gas comes out of as long as you have gas.

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8 minutes ago, baldy110 said:

Again so what so does mine and again the OEM carb works just fine.  Why come on here and ask for advice when you won't take it?  If you already know the answer then why ask the question.

dude what are you talking about. didn't ask you anything. dumb asses like you mess up these fourms. I ask about the pump and people started asking about other things on the bike. 

Edited by whiteXR1
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This post was not pertaining to a bike that was not running well. MY bike runs fine it pulls hard and I'm happy with it.  But there was more power to be made and the lack of gas to the bowls was a problem and i was trying to figure how to fix that. 

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1 hour ago, whiteXR1 said:

yea my main jet is 175 and  the fuel petcock is a stead stream. But keep in mind i have port polish,  larger valves ,3angle  job,  stage one cam , and port flow on the head. and it still bogs a little bit when I'm cruising and then i hit the throttle WOT.

If those are Keihin jets, I bet your problem is that you're too rich.  (If the jets are from DynoJet, who knows?)  I have a 158 main jet in mine, at sea level, and even that is on the rich side.  I would be surprised if you need bigger than a 160.

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3 hours ago, whiteXR1 said:

their is no adjustment with the oem carb 

Funny. All Keihin and mikuni carbs have adjustable floats. They have to be set properly. Even the manual for this bike says so. But you do you bud. Good luck with that electric fuel pump. 

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2 hours ago, ScottRNelson said:

If those are Keihin jets, I bet your problem is that you're too rich.  (If the jets are from DynoJet, who knows?)  I have a 158 main jet in mine, at sea level, and even that is on the rich side.  I would be surprised if you need bigger than a 160.

Sounds right. Big bored bikes pull more vacuum and suck more fuel through the jets. So a larger jet would be too rich where as you'd need to drop a size or two from stock jetting on pilot and main jet. 

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6 hours ago, Brad04 said:

Funny. All Keihin and mikuni carbs have adjustable floats. They have to be set properly. Even the manual for this bike says so. But you do you bud. Good luck with that electric fuel pump. 

The stock carburetor for the XR650L is a Keihin, and the float is not adjustable.  Your information isn't quite right.

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so i went ahead and put the fuel pump to the carb and it seems to be making more power  the clutch it slipping at WOT so I do know the full amount of power yet  I have not put a return line but its not flooding at idle. the plug is now telling its a little rich now i can go down on the on the main jet. will be getting more stuff for the end of the week. ALSO THE VALVE COVER LEAKS OIL NOW, JUST A LITTTLE BIT. I GUESS ITS FROM THE HIGH REV IM GETTING NOW WITH THE FUEL PUMP.

HERE IS HOW IT LOOKS BUT IT NOT FINISHED IDK IF IM GOING TO KEEP. 

IMG_0999.JPG

IMG_0998.JPG

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21 hours ago, whiteXR1 said:

Im going to install and let you know the out come. Their is methods on installation to make a return line so the bowls don't flood when the  bike is at idle. i know from shifter cart experience  it gives a 3 times better throttle response with no lean conditions. 

I've never checked the pressure those pumps produce but I know the Polaris stuff I've replaced them on didn't have a return line or a pressure regulator.  They were straight from the pump to the carb inlet.  The needle and float didn't appear to be anything special.  I'm not exactly sure how they work.

 

The pump you're using is a little different that what I've worked on.  Same concept I guess.

Edited by Hollerhead

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8 hours ago, Hollerhead said:

I've never checked the pressure those pumps produce but I know the Polaris stuff I've replaced them on didn't have a return line or a pressure regulator.  They were straight from the pump to the carb inlet.  The needle and float didn't appear to be anything special.  I'm not exactly sure how they work.

 

The pump you're using is a little different that what I've worked on.  Same concept I guess.

yea its only 14 lpm. going to do  the return line then re jet. It made more power. and it revs faster now. 

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