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Johnnykind

XR650R Edelbrock pumper Pump shot question

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OK first the specs I guess,  2000 XR650R  

102mm Piston, Stage 2 hotcam

Edelbrock Pumper carb, Oversize valves,  intake and exhaust +3mm intake +2mm Exhaust

Figures,  I just posted something about how well my Edelbrock was running now I have problems... Go figure...

Just got the whole top end back from the shop, everything is pretty fresh Engine wise... Blew a head gasket last year finally got it fixed...

Now the Problem,  when the bike is idling, I blip the throttle quick, Rpm' s go up and don't come back down, stay at about 3000-4000

another blip of the throttle and the R's come down almost back to idle, about 2000 and slowly drop back to an idle from there...  

10 years ago the stock carb was doing the same thing, so I upgraded to the edelbrock, Ran like a champ from the day it was installed...

Now its doing the same thing, Could this be too much pump shot ???  Does that even have anything to do with it ??? 

I know all the Edelbrock Haters will just say get a new carb, just spent  $1000 at the shop, No money$$$ left for a new carb, Besides I really like this one especially when it is not doing this !!!

Thank in advance for the help !!!  

Sorry about the blurry pic... it looked good on my phone 

20190414_161026 (1).jpg

Edited by Johnnykind

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Hey Johnnykind,

I have an Eddy on my XR650R but haven't needed to adjust it yet. But, hanging idle to me screams lean pilot. Assuming there are no vacuum leaks try richening the mixture with the knob. You can always turn it back. I would think if it was lean or rich on the AC pump shot it would bog.

Edited by ericsXr600R
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2 hours ago, jetfuel said:

 i see you got it sorted in the other post

Yes, 

*** Update***   

adjusted pump shot 2 1/2 turns out from seated 

3 clicks right on the enrichment screw, and like magick hang idle was gone !!!

Still have Bog from 0-1/3 throttle stumbles a bit.

and now has a really weird issue !!!    Feels like a kind of vapor lock ?!  

Past top dead center, Release the compression lever, kick it half way thru and it comes to a dead stop.... just about broke my foot !

Like there is a second compression spot half way thru the kick ????   Any body else ever had this ?

My buddy down the street has the same problem and he is running the stock carb !?

 

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3 hours ago, ericsXr600R said:

Hey Johnnykind,

I have an Eddy on my XR650R but haven't needed to adjust it yet. But, hanging idle to me screams lean pilot. Assuming there are no vacuum leaks try richening the mixture with the knob. You can always turn it back. I would think if it was lean or rich on the AC pump shot it would bog.

Yes Sir,  that's exactly what it was Too lean...

Still working on dialing in the pump shot.... but that Damn Hang Idle went away...

now I got this vapor / compression spot issue, half way thru the kick, it comes to a dead stop !

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I didn't say jet. Someone else did.
I still think air leak. It's carbureted. There's no mechanical fuel pressure. So if it's not getting extra fuel(without opening throttle, introducing more air, demanding more fuel pull) then it's more air than fuel AS IF the throttle was being held open, or closed slowly. But when it's already been fully closed. That's air. A minute crack somewhere...or something. It's air that's asks for more fuel. When there's more air the carb gives the fuel and you are not at idle rpms...
But bikes not in front of me.
Best of

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7 hours ago, notoriousE-R-I-C said:

I didn't say jet. Someone else did.
I still think air leak. It's carbureted. There's no mechanical fuel pressure. So if it's not getting extra fuel(without opening throttle, introducing more air, demanding more fuel pull) then it's more air than fuel AS IF the throttle was being held open, or closed slowly. But when it's already been fully closed. That's air. A minute crack somewhere...or something. It's air that's asks for more fuel. When there's more air the carb gives the fuel and you are not at idle rpms...
But bikes not in front of me.
Best of

went back and Double checked for air leaks, everything is sealed up tight... After adjusting the enrichment screw, and the Pump shot, the Hang Idle Disappeared... 

Still can't figure out this hard spot in the kick tho... like a second compression spot in the middle of the kick, just comes to a dead stop.   

Didn't do it this morning, started right up first kick,  Hurt the hell outta my foot yesterday tho, Dang! 

Seems like it only did it when I bliped the throttle before starting, but the manual says to do that on a cold start ?  (Gone this morning hopefully stays gone)     

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On 4/16/2019 at 3:30 PM, Johnnykind said:

 

Still can't figure out this hard spot in the kick tho... like a second compression spot in the middle of the kick, just comes to a dead stop.   

Didn't do it this morning, started right up first kick,  Hurt the hell outta my foot yesterday tho, Dang! 

One of my pigs has a built motor from XR’s ONLY with cam and it can do the same thing. I believe it’s because you lose the auto decompression of the stock cam when going to an aftermarket performance cam. If I don’t set the motor in the perfect spot for starting, then it stops hard at the half way point of kicking it through. My other pig is stock, and I can start it in flip flops. Moto boots only when starting the built motor!

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I was in the same boat. My '03 ran great then probs. Even my friend the mech couldn't figure it out and parts??? Finally just put on a Lectron and Voila! Had then on my 2 stroke mx bikes years ago and they are the bomb. Now I ride from the beach to 10K mountains here no problema and better gas mileage. And peace of mind no problems out wherever I am! Glad u got yours sorted out!

Edited by hockeyrick
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4 hours ago, hockeyrick said:

I was in the same boat. My '03 ran great then probs. Even my friend the mech couldn't figure it out and parts??? Finally just put on a Lectron and Voila! Had then on my 2 stroke mx bikes years ago and they are the bomb. Now I ride from the beach to 10K mountains here no problema and better gas mileage. And peace of mind no problems out wherever I am! Glad u got yours sorted out!

Thanks bro,  for sure, I have really been considering a Lectron, once I tried a few things I was surprised how quick the eddy was to tune..

3 clicks on the enrichment screw, re-seated the pump shot screw and turned it out 2 1/2, and Bam... she fired right up and the hang idle was gone 

to tell the truth there was a can of carb cleaner in there too !!! but mostly just screwing around with the screws...lol

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6 hours ago, bajabinder said:

One of my pigs has a built motor from XR’s ONLY with cam and it can do the same thing. I believe it’s because you lose the auto decompression of the stock cam when going to an aftermarket performance cam. If I don’t set the motor in the perfect spot for starting, then it stops hard at the half way point of kicking it through. My other pig is stock, and I can start it in flip flops. Moto boots only when starting the built motor!

That is what I was thinking too, Big Piston, Big Cam, Big Valves, big hard kick start,  but usually like you said I can kick it over in flip flops... 

Talked to my buddy last week about his 650r and he is having the same kick start problem, his bike is pretty stock except for being Un-Corked

Gotta be some kind of, carb issue, he had the hang idle too, so he tried some other advice plugging off a port in the carb ?!?  now he has the hard kick problem adjusted his valves half a dozen times, still the same... I noticed with mine if I pulled the plug and kicked it a few times that Vapor lock feeling went away and it kicked over normally after that...  Thanks so much for your input, nice to know I am not the only one having these weird problems ! 

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On 4/16/2019 at 3:47 PM, notoriousE-R-I-C said:

The manual is telling you that with a stock carb.
If no air leaks, then fuel is still squirting.
Sounds like you're finding the right settings.

Sorry I meant the Edelbrock manual says to give it 2 blips for a cold start...  Every time I did it would stop halfway thru the kick. 

So now with no blips, on a cold start, Fires right up... No hard spot...  Weird 

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