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Popping on deccel

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I'm running the full power up kit. 115 main, 42 pilot, need at 4th clip fuel screw 1.5 turns out plug tan. But like if I'm going in 2nd or 3rd gear and let off the throttle it pops like 2-3 times not like a backfire pop though.

So, I'm wondering what is causing it. it seems to do it more during cold weather though so that might mean something. Also, I have not adjusted my valves since I have got the bike (almost a year ago now)

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Your running on your main jet or needle in 2nd and 3rd and suddenly you chop your throttle and your motor is still trying to suck a main jet amount of fuel thru your pilot jet----lean,lean,lean. Try adjusting your idle mixture screw another haft turn rich and see what happens or learn to let off on the throttle easier.

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Your running on your main jet or needle in 2nd and 3rd and suddenly you chop your throttle and your motor is still trying to suck a main jet amount of fuel thru your pilot jet----lean,lean,lean. Try adjusting your idle mixture screw another haft turn rich and see what happens or learn to let off on the throttle easier.

Agreed, same problem. make sure you get your bike up to operating temp before you check results. My KLX pops a lot until its warm-even when properly jetted.

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use higher octane fuel, it sez it in you owners manuel"92 octane or higher with no lead ":lol:

No.... Do you realy think I'm that stupid??? :)

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The popping is excess fuel igniting in your exhaust pipe. If it's from full throttle let off then your main is too fat. 1/2 throttle let off then your needle is fat.

Good advise from the others about making sure it's warm. If it's just a little popping then I wouldn't mess with it. A small amount of "fat" popping doesn't hurt anything.

You might want to try a 112 main jet. For $4 & 10 min time you don't have much to lose.

:)

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Could it just be the cold weather???

No, cold weather would lean it out & decrease fat popping.

BTW it only pops like once or twice on decel

Somebody said, "a small amount of fat popping doesn't hurt anything."

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A lean condition creates the popping on decel. Backfire is rich. Due to the cold weather, you may be too lean. Go out with the fuel screw about 1/4 turn and it should go away.

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noob_with_150, check ur clamp that tightens down ur intake into the carb, and the exit out of the carb into ur engine. (those black plastic things that ya have to remove to spin the carb around) They might be loose, sucking air and causing it to be lean.

Poping usually means lean.....blubbering usually means rich.

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Backfire is lean.

Why is it that when we put a new exhaust, why does it pop, not backfire? It's jetted lean.

With my 230 and Yammie, they first popped on decel. On the 230 I went up on the pilot, and on the Yammy, I went out with the fuel screw. No pops on decel.

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It's a small backfire you're hearing & yes, more fuel is the cure. Thats' not the situation here though.

The fat popping is unburnt fuel igniting in the exhaust. As with the jetting for the 230 I'm sure the jetting for the 150 is TOO fat on the main jet. Smaller main jet will decrease the popping he's getting.

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If popping on decel is from being rich why does my DR350 quit popping when I richen up the fuel screw? A backfire is from being rich, thats why they put backfire screens in air filters, so you don't burn up or melt your air filter.

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So many experts in here. So now a backfire is from being rich.

You guys get him going in circles if you want.

I'll say it one last time with real small words. :) Backfire is almost always from a lean condition. Slightly lean will create baby backfires that some people call popping but it's different then the popping you get from being jetted too fat. Fat popping is a small explosion of excess fuel in the exhaust pipe.

More on the backfire. Why does lean condition cause a backfire? There could be more to this but here's part of it: The lean mixture burns faster & hotter. It's fast enough to actually make it's way out of the cylinder via the intake valve before it closes completely looking for more fuel to burn. A fat mixture burns slower & cooler & therefore tends not to "backfire."

:)

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In my previous post I do not mean to imply I'm an expert about anything. I just make $hit up! :) j/k Seriously, I'm not certified. :p

Hey Creswellelkhunter, that is the coolest nicest DR350 I have ever seen! :) Nice ride!

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I'm a little confused... I have the same issue on my Girls bike. It has a very distinct POP-ing at decel. If i go past about 1/2 throttle and let off it will pop. I have a 145 Main/ needle is in the 4th clip... (alittle rich) and the pilot is a 47 and about 2 turns out on the screw.

The bike ran very well this winter, but now it is starting to POP more as the weather warms up...

Is my set up too LEAN now or Rich... and just for the record. To twist the screw TIGHT is RICHING the bike??? right?

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Hum, you have a 230????? a 140 something is huge!!!! altho it was probaly setup for ur climante. on the fuel screw, rich is out, in is lean. :)

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I'm a little confused... I have the same issue on my Girls bike. It has a very distinct POP-ing at decel. If i go past about 1/2 throttle and let off it will pop. I have a 145 Main/ needle is in the 4th clip... (alittle rich) and the pilot is a 47 and about 2 turns out on the screw.

The bike ran very well this winter, but now it is starting to POP more as the weather warms up...

Is my set up too LEAN now or Rich... and just for the record. To twist the screw TIGHT is RICHING the bike??? right?

If her bike is a 230 it's definately too fat on the mainjet. I'd bet Ride_for_Red's bike on it and Red is correct on the "fuel screw."

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