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two Q's regarding pilot circuit

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First off, what is everyone using to seal their exhaust. I tried copper RTV and still have ALOT of popping. The claimed temp range is far lower than exhaust temperatures, leading me to believe it doesn't work that well.

Second, what is the importance of the proper setting of the pilot circuit? I have been fighting decel popping for too long on my Husky. (07 TE 450) I have an external adjuster to fiddle with, and after reading several posts on the subject I went to town on the pilot circuit. It doesn't seem to matter what jet I install, the RPM doesn't change by any appreciable amount. For experiment sake I went small and I can't find a pilot jet small enough to make the bike stall with the screw all the way in. The next step down is a 38, which none of my locals stock, and is ridiculously small anyway. So then I thought, 'F' it. I'm going rich. I put a 50 in and the RPM still doesn't change much. If I back the adjuster out 4 or 5 turns, the bike stalls it's so rich.

I test rode it with the 50 in and the adjuster out .75 turns. the bike still pops alot, but there seems to be no difference in rideability. throttle response is great, and as an added bonus, I don't need the choke to start it after it sits for half an hour.

What it really boils down to for me is; 1) any idea what it could be, and 2) aside from higher fuel consumption, does it really matter how the pilot is set, if it's not bogging out when I hit the throttle?

The particulars are:

2007 Husky TE 450

JD jet kit. 185 main, 50 pilot, red needle 5 position. JD supplied leak jet w/ o-ring on acc pump.

powernow and powernow plus

uncorked stock exhaust.

rekluse clutch

external air screw adjuster

Thanks for opinions

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The reason Eddie is asking that question is a lot of folks have put the front piece (vacuum release plate) in upside down, idle is eratic, slow to drop to idle, phun meter hangs very low.

My 05 TE450 Husky was the one JD used to make up his initial kit for these, he showed me a target F?A mix on a meter and could not get there until we got down to a 42 pilot.

Next issue is who said decel poping had anything to do with the carb? It was not me, not JD and I don't think it was Eddie.

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No, I've never taken the slide completely out.

"Next issue is who said decel poping had anything to do with the carb? It was not me, not JD and I don't think it was Eddie."

Isn't it a widely held belief if you are too lean on the pilot you will pop on decel?

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Sometimes, opening the fuel screw a bit more will reduce decel popping.

When the eninge is zipping along and you close the throttle, an extremely lean mixture (for the engine speed) is created. Often, this mixture will not burn on every power stroke, so it go out the exhaust header. Then perhaps, the next cycle does burn. The flame front ignites the mixture in the pipe, causing a 'pop'. If many cycles occur without a burning in the engine then finally one happens, all the accumulated fuel in the pipe burns, causing a backfire/explosion. A little extra provided by a more open fuel screw can prevent the multitude of non-burning cycles and therefore the backfiring/explosions.

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I have to say a big THANKS to eddie. I just took my 37mm for my 400 and replaced it with a 39. Have been scraching my head for the last 3 days trying to figure out why I can't get it. DUUU the slide plate was up-side-down.

Thanks again for TT and Eddie

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