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88cc Jetting

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I have a 2005 CRF50 with a Trailbikes 88cc kit and Pro Circut exhaust. I purchased this bike like this and it has a really bad bog. It has a ShengWey 20mm carb with an 89 main jet and a 35 pilot jet. I have played with the air screw and played with the needle and can't get it to run right. I also did a search and couldn't find what I was looking for. Does anyone have any jetting suggestions?

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A baseline to start from is the jet needle in the 3rd or 4th notch, air screw turned out 1-1/2 to 1-3/4 turns from seated, and a clean oiled air filter. Most times, you have to turn the air screw IN to richen it, do this is 1/4 turn increments, ride the bike, and see how it performs. Out of the box, with the 89 main and 35 pilot jets, I've sometimes had to run the air screw IN until I was a 1/2 or 3/4 from seated. You can buy a main jet and a pilot jet kit from TrailBikes if the adjustments do not help you.

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Bump...Im having the same problem and am wondering if its from my 90 main jet. Im not sure what size pilot jet I have in it now.

Anyone have any help for us!

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Do you have the 'race head' also?

If so, then you might need to go richer

what is your elevation?

My bike runs a race head setup with stock head pipe to a different muffler, and it runs perfect with the stock carb setup

However if you DONT have a race head, I'd imagine you are too rich.. If you do have a race head, since you have an exhaust, you might be too lean

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It has the race head, BBR exhaust with a 90 main (not sure of the pilot). The clips is now on the 2nd from the top......I think I need a 92 main and 38 pilot....who knows though.

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