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50 pilot jet?

14 posts in this topic

i'm getting alot of popping on my 06 yz450f. the shop didn't have a 45 or 48 pilot jet, the only thing they had was a 50. does anyone run that? if yes, which main jet do you have in. thanks in advance.

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Have you tried adjusting the Fuel Screw first?? Sometimes just turning it out (richening) will eliminate popping.

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i'm getting alot of popping on my 06 yz450f. the shop didn't have a 45 or 48 pilot jet, the only thing they had was a 50. does anyone run that? if yes, which main jet do you have in. thanks in advance.

ZipTy recomends and uses a 48 on their 06 bikes with stock exhaust.

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just for giggles, i put in the 50 with a 170 main. no worky. i'll run the 45 with a 165 or 170.

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I wouldn't run larger than a 45, myself.

can you do damage wiht a 50? or just foul the plug.

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can you do damage wiht a 50? or just foul the plug.

No, just a lot of bog in the throttle

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sounds right. it stalled when i took off, then didn't start. how much do you adjust the fuel screw when you change your jets?

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I wouldn't go any richer than a 45 either. I tried the 48, 170 combo because of advise given here and it just didn't work for me. In the winter I ran a 45 and 168. Now that it is warmer I am back to stock jetting but with the Zip - Ty carb mod and it is very crisp with very little popping. There is a sticky over on the jetting forum that describes how to set your fuel screw and choose the correct pilot jet.

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ZipTy recomends and uses a 48 on their 06 bikes with stock exhaust.

JD also said to put it on clip 5 and it actually runs much better on clip 4...

If you want to know what it's like, turn out your fuel screw a turn or two. EXACT same thing as getting a larger pilot jet.

The pilot jet is just used as a coarse adjustment. The fuel scre as a fine adjustment. You should change pilot jets to get the turns out on the fuel screw 1-2.5 turns out...

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i actually raised the needle one clip and was getting popping. i'll try a 45 and mess with the fuel screw.

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The needle doesn't affect decel popping. It's caused by the idle being on the lean side, or an air leak in the exhaust. IMO, when a YZF is jetted right, it will pop on decel at least a little. To me, it's a sign that I'm too rich on the pilot when it won't at all.

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thanks gray. i pulled off my pipe and resealed it the other day after riding. i'll go back to stock for now and of course get a new plug. hahaha.

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well, i got my floatbowl out and discovered why my bike wasn't starting...the pilot jet was floating in gas. i've never had that happen. i tightened it, but it came loose.

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