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Clean carb now way too rich CRF250R 2005

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Hi There, 

I always had issues with the bike having a bog when accelerating. but the bike was running "OK" and starting first kick

I looked online and bought a quickshot 3, I could have done it slowly with just changing the leak jets but I don't have a place to ride the bike, so every time I've got to pay to get to a track.

to cut long story short, I took the carb out, cleaned it and installed the QS3 

Slow jet 42

Main Jet 172

Needle 5th grove (stock 3 but as mixture was ok I did not want to change too many parameters at once)

Put everything back together and went to the track. 

Very odd I could not start the bike with the choke on. Then I tried with only the hot start and it started first pop (from cold)

Then went riding. It was really bad, the engine would blubbers everytime I was between 0-1/2 throttle, then above that it would run lovely.

Do you think the chances are I didn't put the carb back in right? I tried every adjustments possible didn't make a difference. fuel screw all the way in, same problem, fuel screw 3 turns out same, and every combinations in between. 

by the way the bike starts at pretty much every kick as long as I use the hot start. 

Let me know what you think.

Cheers

 

 

 

Plug before and after carb clean.JPG

Edited by Vincecrf

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If I understand correctly, you moved the needle clip from 3rd to 5th? That would richen the mixture at 1/4 throttle causing your burble. You need to double check the float level height didn't get knock outt of whack also.

 

If the fuel screw has absolutely zero affect than the idle is too high and your running off the needle instead of the pilot. Turn the idle down a bit than adjusted the fuel screw again. Remember, you adjust the fuel screw to get it to idle at the lowest possible​ RPM. 1 turn out or less you need a smaller pilot, 3 turns out, you need a bigger pilot.

 

 

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Hi TT Addict,

Thanks for your quick reply

I did not move the needle position. as the bike was running alright before cleaning the carb i kept it as it was. (I bought the bike not that long ago, redone the top end  

I will now take the carb out again, and check float level make sure nothing is blocked and set the needle back to stock.

I let you know how it goes.

Cheers

Vincent

 

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Quick update,

I managed to find some time last night, too the carb out and had a thorough look at the lower part. 

The main jet, jet needle starter jet and slow jet were clean an secure. 

I measured float height at 8mm which is stock.

I notice that the slide was always slightly open because of the idle being screwed quite a lot in.

I will tonight reset the needle to stock and try to start with the choke on.

I ll let u know.

Vince

20170619_222501.jpg

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Hi there,

After cleaning the carb one more time and changing the needle position back to stock. 3rd clip from the top.

I went riding this weekend, it was very hot (for england) 30C. 

The bike started without choke and rode very well. A slight adjustment of the quickshot 3 got rid of the lean bog.

However the bike became hard to start between session. A few rapid quick without hotstart got it started but not the usual 1 kick with hotstart.

I checked the valve today, they are all ok exactly on stock value. 

Is there a way to know if the bike is too rich or too lean to start? Should i try a few quarter turns in or out on the pilot jet?

Cheers

Vince

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Hi there,

After cleaning the carb one more time and changing the needle position back to stock. 3rd clip from the top.

I went riding this weekend, it was very hot (for england) 30C. 

The bike started without choke and rode very well. A slight adjustment of the quickshot 3 got rid of the lean bog.

However the bike became hard to start between session. 

IMG-20170710-WA0009.jpg

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