Polini CP Idle Jet?

Excuse my poor searching if there is already a thread, buttttt

What range are you running your idle jets in? I'm just trying to get a base line for 17.5-23mm cp's, the 21mm CP I'm running on a 64cc Tomo has the stock idle jet, and it's staying forever as the damn thing shore it's flange when I went to remove it, it being a 40 is clearly to large. Yeah I could buy some ranges and start stepping down until I'm happy with it, but a little insight from anyone who has done this prior to me would be cool!

Re: Polini CP Idle Jet?

no one? Really?

Re: Polini CP Idle Jet?

Always wanted to try one but never bit the bullet yet. They look quality.(edited)

Re: Polini CP Idle Jet?

DrGeorgeTompson (Alan) /

can i get an english translation of this:

> and it's staying forever as the damn thing shore it's flange when I went to remove it, > it being a 40 is clearly to large

I was running like a 34 or 36 on a 70cc piston port with a 21CP. I am now running it on a 50cc AM6 motor at 40. You're better off just buying the 5 pack of idle jets. Can you even buy them in singles?

They are nice carbs though.

Re: Polini CP Idle Jet?

this might be obvious, but i always tune these by going off the screw, on the PWK clones it is an air bleed so if i'm less than 1/2 turn out (going in is richer) i go down a pilot jet, if i'm more than 2.5 turns out (lean) i go up a pilot jet. if it makes no damn difference at all i just swap parts wildly until it does.

i can't give you the answer you want because i haven't played with the polini specific ones yet, but 32-38 seems to work for every single pwk style carb i put on a moped.

i'm still figuring them out, trying to tune in a 24 joko on my tccd 70, but the needle seems to really rule the roost, clip changes make a huge difference. I just bought a new genuine oko needle and atomizer. Your results may vary though because i'm on a cretin-ported piston port with zero midrange, and you're on a bike that is going to have a much flatter vacuum signal.

good news is that all the PWK clones seem to be super stable jetting wise, there are really only about 3-4 pilot sizes and jet sizes that apply to mopeds, i'm not totally scienced out on the needle thing yet but from what other people have posted, it seems like the needle and atomizer that comes with them work for most setups.

let us know how it goes, i'm gonna put another joko 24 on my parmakit a35 next.

Re: Polini CP Idle Jet?

DrGeorgeTompson (Alan) /

> Graham Motzing Wrote:

> -------------------------------------------------------

> if it makes no damn difference at all i

> just swap parts wildly until it does.

This was my experience with the PP kit. I probably lost some sleep over that

Re: Polini CP Idle Jet?

haha yeah i've been from 20-50 on the pilot jet, i've tried 3 different needles and two atomizers, and 110 to 150 on the main. then my needle bearing explodered and that was that, dying to get back on it.

it was really shocking how little difference some of the huge changes made... these carbs just, like, work... getting them dead nuts perfecto becomes really hard because they aren't like a PHBG that tells you its unhappy.

i'm gonna try the new genuine oko needle and atomizer with the 110 main and the 32 pilot when i get it back together. i think thats going to be getting me real close. pilots from 38-50 all basically ran exactly the same, not happy but still running and really not as terrible as you would think.

Re: Polini CP Idle Jet?

> Graham Motzing Wrote:

> -------------------------------------------------------

> haha yeah i've been from 20-50 on the pilot jet, i've tried 3 different

> needles and two atomizers, and 110 to 150 on the main. then my needle

> bearing explodered and that was that, dying to get back on it.

>

> it was really shocking how little difference some of the huge changes

> made... these carbs just, like, work... getting them dead nuts perfecto

> becomes really hard because they aren't like a PHBG that tells you its

> unhappy.

>

> i'm gonna try the new genuine oko needle and atomizer with the 110 main

> and the 32 pilot when i get it back together. i think thats going to be

> getting me real close. pilots from 38-50 all basically ran exactly the

> same, not happy but still running and really not as terrible as you

> would think.

Graham, you gotta give the Polini needles (and jets for that matter) a try. Totally transformed my OKO. The JJN needle is the best one I've found. Totally magical for mopeds

Re: Polini CP Idle Jet?

i have had to drill out an air jet on one to get it lean enough to run one of those space filter boxes. 32 was not quite low enough for a 50cc

Re: Polini CP Idle Jet?

DrGeorgeTompson (Alan) /

But doesnt the CP have that little removable plug to add more air or something? or is that what you drilled?

i know it says for 2/4 stroke but I dont really know what it does cause the manual is translated all crap like. I took mine out for a while. Made it a lot leaner but i ended up putting it back in at some point.

cp_polini1ing_LI.jpg

Re: Polini CP Idle Jet?

Yeah take the air brake jet out. Treats has air brake jets too.

Re: Polini CP Idle Jet?

> Ryan N. Wrote:

> -------------------------------------------------------

> Yeah take the air brake jet out. Treats has air brake jets too.

Take it out and just leave it open? Or plug it?

Re: Polini CP Idle Jet?

DrGeorgeTompson (Alan) /

> Toledo Riot Wrote:

> -------------------------------------------------------

> > Ryan N. Wrote:

>

> > -------------------------------------------------------

>

> > Yeah take the air brake jet out. Treats has air brake jets too.

>

> Take it out and just leave it open? Or plug it?

It comes plugged. try taking it out.

i feel like i had to upjet the idle a shit ton after taking it out. Idk it's been a while.

Re: Polini CP Idle Jet?

I use a CP 17.5 with 52 pilot / 76 main / 32:1 premix.

Rich pilot circuit and needle clip position reduces piston temperatures at high rpm / low throttle slide position.

Re: Polini CP Idle Jet?

Ok, 73cc Polini'd V1 with a 4 petal reed block, 24mm intake, Polini CP, 10x36 gearing

Main 106 or 116 I honestly cant read it

Idle 38

I hit 49 with it the other day, with room left, it was 28 degrees and I thought I was gonna turn into an icicle, but it idles great, throttle response is much better then the sha it replaced, and my temps maxed out at about 280, I'll report back more when it warms up a bit!

Re: Polini CP Idle Jet?

take the air brake jet out. you might have to richen the needle and the main but it'll feel better.

Re: Polini CP Idle Jet?

> Ryan N. Wrote:

> -------------------------------------------------------

> take the air brake jet out. you might have to richen the needle and the

> main but it'll feel better.

I will give this a try for sure, in a classic Ohio move, it has been in the 40's the past few weeks, but today we are getting dumped on with snow....

Re: Polini CP Idle Jet?

Ok, I think I have figured this air brake business out. For two strokes using the CP, you need to COMPLETELY close the air brake hole with one of these.

https://www.treatland.tv/polini-CP-air-correction-jet-closed-p/polini-cp-air-correct-343.0750.htm

The Polini manual is difficult to follow, but here is the gist. The Polini CP comes with a "four-stroke" style atomizer (the ones with little holes in them). The air brake jet is to adjust the air coming in to mix with the fuel sucked in by this atomizer. The manual states that this opening needs to be CLOSED for proper operation in two-stroke motors.

Re: Polini CP Idle Jet?

Hi Andy,

I know it's an old thread but have you got it all figured out? I'm leaning toward a Polini CP 19mm for my Polini'd V1 (also with a 4 petal reed block). What size is yours?

I'm trying to ballpark jet sizes so I don't have to buy a whole lot of ranges but they are not that common among V1 users as far as I can tell.

Thanks!

Re: Polini CP Idle Jet?

> Guillaume Guite Wrote:

> -------------------------------------------------------

> Hi Andy,

>

> I know it's an old thread but have you got it all figured out? I'm

> leaning toward a Polini CP 19mm for my Polini'd V1 (also with a 4 petal

> reed block). What size is yours?

>

> I'm trying to ballpark jet sizes so I don't have to buy a whole lot of

> ranges but they are not that common among V1 users as far as I can tell.

>

> Thanks!

Ive stuck with the above settings for my V1, its hitting mid 50's and all seems well, Ive also been running these carbs on some Moby's lately with great success, Ive been around the same jet range with those, however they are much higher reving, and slightly less cc's, 100-120

Re: Polini CP Idle Jet?

finally piked up a CP19 to put on my puch polini, excited to check it out

Re: Polini CP Idle Jet?

DrGeorgeTompson (Alan) /

I ended up grabbing another 21mm CP and it's on my Flatreed.

47mm "Metrakit" airsal job

MLM reed block intake thing

Malossi x360 Intake

And some shitty emgo cone filter thing that's lightly oiled

Jetting is currently 34 idle 105 main. i think i'm one clip leaner of the middle on the needle.

I wish i could find a leaner slide but there is only a richer slide. 1/8 throttle is pretty fat but it's ridable. Seems pretty lean at low throttle hi rpm but i make do

Good carbs and i feel like they are pretty forgiving to tune.(edited)

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