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Bogging problem

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Okay so Last night I installed a JD jet kit and my bike was still bogging when getting on the throttle hard but pulled like crazy when rolling on the throttle. The bike starts fine and idles great so I know the pilot and fuel screw are close. I need help on getting rid of that bog pretty quick since im going riding this weekend. The Bike is a 2007 Honda crf250r all stock minus SS valves and jd jet kit.

Weather and Altitude:

~60* at sea level

Jetting specs:

170 Main

45 Pilot

JD Blue needle with clip at 3rd position

40 leak jet.

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Okay so Last night I installed a JD jet kit and my bike was still bogging when getting on the throttle hard but pulled like crazy when rolling on the throttle. The bike starts fine and idles great so I know the pilot and fuel screw are close. I need help on getting rid of that bog pretty quick since im going riding this weekend. The Bike is a 2007 Honda crf250r all stock minus SS valves and jd jet kit.

Weather and Altitude:

~60* at sea level

Jetting specs:

170 Main

45 Pilot

JD Blue needle with clip at 3rd position

40 leak jet.

You need to service the accelerator pump system with a service kit:

- new diaphragm

- new spring

- new orings

- clean the passage up to the apump spray nozzle.

http://www.jdjetting.com/xcart/product.php?productid=135&cat=0&page=&featured=Y

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ive never heard of this recommendation before. Any other ways to get rid of this jetting wise?

Are you asking if you can fix your accelerator pump without fixing your accelerator pump?

When you twist the throttle, the apump squirts gas directly into the head, so you won't get momentary fuel starvation at low rpms (low vacuum). When the Apump is not workig right, you get bog.

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Well...I guess the AP squirt was hitting the slide a little bit. I turned the AP timing screw out a little bit and the bog went away. Thanks for your help, this bike is now sooooo much more responsive.

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A 40 leak jet seems a little small. I wonder if that is what messed up the ap timing. Most are running a 50 or bigger. On another note. If you go to the honda crf250 forum here you could have asked and gotten the exact jetting you need and gone to your dealer and ordered all the jets for less then half the price of a kit. Most people here are more then willing to help you set it up right.

Glad you got it going. :)

Jetting for most crf250r's is: 40-45 pilot, 170-172 main, stock needle with the clip in the 3rd position, 50 leak jet.

:lol:

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Yea I was also going to say @ sea level that 40 seems a bit too lean....You DON'T want lean. That quick responsive throttle can be deceiving man because it is also a lean symptom...Lean jetting will ruin a motor. Most guys actually find out what jetting is too rich, and go a size right under that. Always better to be on the rich side vs. lean...Just my .02

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Yea I was also going to say @ sea level that 40 seems a bit too lean....You DON'T want lean. That quick responsive throttle can be deceiving man because it is also a lean symptom...Lean jetting will ruin a motor. Most guys actually find out what jetting is too rich, and go a size right under that. Always better to be on the rich side vs. lean...Just my .02

Leak jet jetting is actually the reverse of normal jetting. The smaller the jet the richer the fuel shot from the AP. A smaller jet forces more fuel threw the AP circuit.

On that note you can also get a bog from too rich of a squirt from the AP. I experienced this this last summer when I went with a 50 leak jet like everyone recommends. Bike would bog bad when opening the throttle quick. Went back to the 70 leak jet and the problem went away.

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My bike was bogging bad with a 65 and everyone suggested a 45 leak jet. My dealer didnt have that so I got a 40. And I only got the JD jet kit since my stock needle was bent somehow. I thought I might as well just get a JD kit with the custom needles and get the jetting right.

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My bike was bogging bad with a 65 and everyone suggested a 45 leak jet. My dealer didnt have that so I got a 40. And I only got the JD jet kit since my stock needle was bent somehow. I thought I might as well just get a JD kit with the custom needles and get the jetting right.

Dont get me wrong. The kits work but still need some fine tuning.

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