mixture screw on pbhg?

i think my mixture screw needs to be adjusted more ,but when im hitting my powerband and let my throttle down really fast the try to throttle back up it sticks and i have to giggle my throttle to get it to engage, giving me combustion again . any ideas ? i have a motobecane av10 70cc malossi and 19 dellorto 106 main jet and a er3

Re: mixture screw on pbhg?

This is a performance tuning question. Please think about what it is you want to say and state it a little more clearly in the performance forum.

We can't have people polluting the forums with missplaced topics. They are put there to help you receive a faster more focused responce.

Re: mixture screw on pbhg?

well thanks for nothing guy . i didn't mean to pollute your general moped discussion forum by asking questions about mopeds . maybe you let me know what is appropriate for general moped discussion?

Re: mixture screw on pbhg?

just go there with question and change your idle jue, it works in part with the idle screw....idle---air fuel.

Re: mixture screw on pbhg?

Sons of GROMarchy /

Somebody might have the same question as you and when searching, they'll have a harder time because they think, "Oh, this is a 'Performance Section' question." only to find no answer because it's buried in here.

Here's an example of a General Moped Discussion question:

"What type of moped would you recommend for a cross country venture?"

To which somebody would reply with:

"None. Mopeds are fucking stupid."

Re: mixture screw on pbhg?

ian curry Wrote:

-------------------------------------------------------

> well thanks for nothing guy . i didn't mean to

> pollute your general moped discussion forum by

> asking questions about mopeds . maybe you let me

> know what is appropriate for general moped

> discussion?

"Please think about what it is you want to say and state it a little more clearly in the performance forum. "

You make me wish I was rude to begin with.

Re: mixture screw on pbhg?

mixture screw adjusts amount of fuel when on the intake side, amount of air when on the air filter side of the carb body. On PHBG it is on the intake side so adjusts amount of fuel. clockwise will lean your mix, counter clockwise will enrich our mix. I find that the leaner the better (providing it will still idle) in terms of throttle response from take off. PHBG manual indicates that you should be sitting somewhere around 1 and one half turns out from all the way in (if I remember correctly). once you get within a turn or less out from all in, it is time to step down to a leaner idle jet. Currently I am running a #50 idle on my AV10 race bike -- probably a #45 would be better as I am only a half turn out.

Re: mixture screw on pbhg?

thanks for the info

Re: mixture screw on pbhg?

You can reference this if you'd like: PHBG Tuning Made Easy - A step-by-step guide. The wiki pages are full of tons of fun and interesting information. Check it out!

Re: mixture screw on pbhg?

Whatever bozo wrote the step by step guide made it seem way more complicated than it has to be. Ian paraphrased everything you really need to know about idle jets. Most phbgs come with really rich idle jets and its usually best to downjet yr idle.

The symptoms you are describing have nothing really to do with idle circuits though. You are discribing either, a sticky throttle cable (common on pivoting moby engines) or the fact that when you are in your powerband you are consuming maximum gas, and when you suddenly cut your throttle you dangerously cut out your cooling 2stroke mix for a second in a high revving situation. Most seizes happen around this point if the bike is running hot. On a phbg/ and in a performance engine setup its a great habit to open up your choke circuit slightly when deaccelerating from a hot run to compensate for drastic fuel starving. Especially if you are jetted leaner on your mixture for performance Your problem could also be reed related.

Also 106 is generally way too rich of a mainjet for 70cc/19phbg setups. Generally, mid 80's is correct. That could be a compensation for airleaks. Though I'm not an expert on av10 jetting senarios.

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