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lurching/blipping on deceleration?

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So when I compression brake...if you can call it that on a two stroke...the engine keeps blipping..not backfiring..but like someone inside the carb is yanking the throttle a hair after I let off..kinda weird..just thenature of the beast? Changing numerous jettings sizes and needle clip positions didnt have any effect..any ideas?

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Try setting the idle low, so it barely idles and then dies. Next, use a bigger pilot jet, and then richer clip position.

James

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Update..does it with a 45 and a 55 pilot..only two I have tried..although bike with 45 pilot like BURNED reccomended has wicked throttle response, so sticking with the 45, seems no matter what rpm you're at..you whick it open and pretty much zero delay.

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What is the complete jetting you mostly run?

pilot, air screw, needle code, clip position, slide number, and main jet

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I just got the bike two days ago..stock was a 55 pilot and 168 main with 2 turns out and 3rd clip fromt he top..now it has a 162, a 45 and 2nd clip from top and one turn on air screw..same exact things..even if you blip the engine under no load as it winds down through the revs it does a blip of its own right before idle speed.

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3rd clip fromt he top..now it has a 162, a 45 and 2nd clip from top...

The clip position means nothing without a needle code (the stamped letters and numbers on the needle). What is the needle marking code?

It sounds like you have an air leak, lean jetting, or too low of an octane. What fuel octane and oil ratio are you using?

Did you turn the idle speed Down?

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32:1 with 91 octane here at 6000 feet, trust me..it is not lean. I forgot to check the needle number...likely whatever the factory needle was. An air leak is possible as the read cage and carb boot show some age cracks..all of which are getting replaced this week.

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32:1 with 91 octane here at 6000 feet, trust me..it is not lean. I forgot to check the needle number...likely whatever the factory needle was. An air leak is possible as the read cage and carb boot show some age cracks..all of which are getting replaced this week.

Let us know the results after replacement of the carb boot and reed cage.

Check the needle code at the same time.

To explain, R1366N#5 = R1366J#3 = R1366E#1

The code directly relates to clip position and how lean or rich the needle is. A bike can be fat/rich at 1/8 throttle and lean at 1/2 throttle.

I'll aggree that it's most likely rich at 6000ft, but the jetting needs to be evenly balanced at each throttle range or it will be going from lean to rich and back.

James

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