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Scooters - 50cc => Agility 50 => Topic started by: Kenho21 on May 26, 2012, 05:51:03 PM

Title: When to upjet to a larger pilot jet
Post by: Kenho21 on May 26, 2012, 05:51:03 PM
70cc kit, open aide filter and performance exhaust, think I should upjet the pilot? Have to turn the screw pretty far out to get a decent idle...
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 26, 2012, 09:11:28 PM
...have you increased main jet??

..you probably need to raise your needle, bro...

..and with the oem carb, that requires some modifications to the needle retaining clip...and the needle's head...
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 26, 2012, 10:30:23 PM
Yea, the main jet is 105 right now I believe, probably gonna drop it down to a 95-100 though, 105 is rich.

You mean putting a washer around the needle to raise it a little? I did that before but then took it off because I didn't notice any difference.

What kinda mods are you talking about with the needle and the retaining clip?
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 26, 2012, 10:54:18 PM
..i dunno, kenho...but i believe that just a pipe without more air in is sorta counter-productive...
..you up-jetted for the pipe, but the oem airbox can only suck just so much air...

..that's why your scoot is running rich...

...in my experience, replacing the airbox has been the best mod ever on my 4t engines...
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 26, 2012, 11:44:04 PM
The Pilot does need to be changed depending on the set up. Every engine I have built for better flow rate is the reason I say this. The pilot is as important as the main in most cases. If you are more than 1 full turn from OEM mix screw setting you need to change the pilot. You may have the correct ratio of fuel/air but not the right amount.
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 26, 2012, 11:45:59 PM
...4t oem pilot jet screw is 2.5 turns out...
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 27, 2012, 01:41:29 AM
I do have free flow Uni air filter, so upjetting was definitely necessary but not to a 105, my neighbor made me a bunch of sizes and I lost the envelope containing all the others so I'm stuck right not with the 105 until my new ones arrive.

@zombie- Thanks for the tip about being 1 turn out, I never knew that.

@wordslinger- So what about adjusting the needle?

Would adjusting the needle cancel out installing a new pilot or vice versa?
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 27, 2012, 02:03:59 AM
...4t oem pilot jet screw is 2.5 turns out...
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 27, 2012, 02:30:36 AM
I meant 1 turn away from factory OEM setting, so 3 1/2 turns I guess
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 27, 2012, 03:24:21 AM
Would adjusting the needle cancel out installing a new pilot or vice versa?

Yes. The needle controls bleed from the main. If you are too rich lowering the needle fixes it or lean raise the needle to get more fuel. That is a rougher setting. The correct jet is always best.Some times you just get stuck between, and needles make the difference.
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 27, 2012, 06:06:36 AM
Ohhhhh, thanks for the clarification, did not know that
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 28, 2012, 08:02:34 PM
..like z said, itsa good mix throughout throttle that makes best performance..

..on my 08 a50, i always ran best with my needle reised .025"..with k&n, and modified exhaust...

..they all different tho...

Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 28, 2012, 10:20:12 PM
And pretty much the only way to figure it out is with plug chops I'm assuming? ...pain in the ass
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 28, 2012, 10:32:36 PM
Plug chops are the best way but you get an "ear" for jetting in time. The best way to go is get the idle circuit at 2.5 turn using the proper jet, and work on the mid/wot jetting after. That give you time to seat the rings too.
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 29, 2012, 12:51:28 AM
..after a while, when you know your scoot, you do indeed get that ear...
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 29, 2012, 01:28:44 AM
I'm still apprehensive about the Scorpion pipe. I can hear the jetting in Expansion pipes but I never messed with an Infinite Baffle before. Hopefully it will work the same... (sound wise)
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 29, 2012, 01:29:56 AM
...yup...only piping i ever did onna 4t was with a cutting wheel, drill and welder...
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 29, 2012, 01:34:36 AM
4t's are much more forgiving on jetting. The pipe blocks the exhaust vs pulling it out. That is why even different pipes on the same 2t engine require different jetting.
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on May 29, 2012, 01:37:41 AM
..learned that..


..firing on every other stroke does have it's advantages..

       
          ;)
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 31, 2012, 01:08:36 AM
Now, where in the hell can I find a larger pilot jet? I'm having a hard time finding one, are there only two sizes, 35 and 45?

I didn't think this would have me so baffled...
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 31, 2012, 01:15:07 AM
http://www.partsforscooters.com/Welcome?search=jets (http://www.partsforscooters.com/Welcome?search=jets)

Or you can easily drill/solder them. http://www.google.com/products/catalog?client=opera&rls=en&q=torch+tip+cleaners&oe=utf-8&channel=suggest&um=1&ie=UTF-8&tbm=shop&cid=17673349416859235469&sa=X&ei=_MXGT-LHMIf48wTTwbXJCw&ved=0CJUBEPICMAI (http://www.google.com/products/catalog?client=opera&rls=en&q=torch+tip+cleaners&oe=utf-8&channel=suggest&um=1&ie=UTF-8&tbm=shop&cid=17673349416859235469&sa=X&ei=_MXGT-LHMIf48wTTwbXJCw&ved=0CJUBEPICMAI)
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 31, 2012, 01:18:33 AM
That's just the stock size isn't it?
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 31, 2012, 01:19:53 AM
Also, what size should I be investigating with a 72cc BBK, performance exhaust, open air filter setup?
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 31, 2012, 01:36:30 AM
That store has other sizes avail. You should wind up at 45ish. Right now I have a 52 pilot in a 72cc kit. They all react differently. I would suggest getting a bigger/better carb anyway. The OEM is just too small for 70+cc's. 19mm Delorto or equivalent will shine. Tunning is a huge money pit.
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on May 31, 2012, 01:54:39 AM
Yea the money pit thing I understood about $1,500 ago haha.

Cool, I will start off with the 45 then.
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on May 31, 2012, 02:02:40 AM
You will have it right when your idle mix screw is approx 2.5 turns out. That works for most all carbs.
Title: Re: When to upjet to a larger pilot jet
Post by: mono on June 04, 2012, 11:06:13 AM
Quote
Yea the money pit thing I understood about $1,500 ago haha.

Yep,  same over here :-) ...
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 05, 2012, 03:55:15 AM
The sucky part is you can Never get that money back out of it. You Have to love modding or it's a big jerk waste.
Title: Re: When to upjet to a larger pilot jet
Post by: mono on June 05, 2012, 07:05:19 AM
Quote
The sucky part is you can Never get that money back out of it. You Have to love modding or it's a big jerk waste.

I guess it works the same as alcohol and drugs in that way  ;D
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 06, 2012, 05:50:53 AM
EGGZACTLEE!!!

Since that pilot jet size posting I have gone down to a 48, and will go one more step. I should be at 47.
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 06, 2012, 06:22:13 PM
@Zombie- Where are you finding those pilot jet sizes?
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 07, 2012, 05:52:28 AM
http://www.treatland.tv/ (http://www.treatland.tv/)
Mention the forum... I am working on a forum discount. They just need to see the traffic.
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 07, 2012, 05:54:04 AM
If they don't have it they will get it for us... As per Gill. (parts)  Gill tells me he can get any parts we need. Super cool store/guy.
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on June 08, 2012, 02:01:43 AM
... www.jets-r-us.com (http://www.jets-r-us.com) ..
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 08, 2012, 03:05:30 AM
I forget... What is the brand/dimension jet for the AG50 carb?
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 08, 2012, 03:06:29 AM
Kihien 5mm
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 08, 2012, 03:07:06 AM
4mm   my bad
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 08, 2012, 03:11:02 AM
Sweet thx
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on June 08, 2012, 03:13:16 AM
..keihin m5..5mm, you were right th first time z...
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 08, 2012, 05:41:39 AM
OOOps! Hope Kenho checks back before ordering. I just ordered some last week for a cvk carb, and the girl said they were 4, and I corrected her. That 4 stuck in my mind, and I second guessed myself off the Island.
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 09, 2012, 03:20:07 PM
Do any of the dellorto jets work?
Title: Re: When to upjet to a larger pilot jet
Post by: mono on June 09, 2012, 03:49:15 PM
Dellorto "small" (5mm thread) jets have a slightly different thread pitch compared to the Keihin 5mm ones.

They do fit somehow, but there's a risk of twisting the head off or cracking the needle jet because of the increased resistance, so proceed with care....

_If_ (!) your needle jet survives the first few jet changes, it's adapted enough to keep using those Dellorto jets, just don't go back to Keihin type because that would stretch it the other way again, increasing the risk of failure...

Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on June 09, 2012, 04:35:33 PM
..yup, i've used delorto m5 jets before...all i could find local, and the ones i got had a longer head on them..

...i dremelled the head down closer to oem length..

..use some spit or other lubrication when threading jet in, if you go that route...


        ;)
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 10, 2012, 02:00:13 AM
Sounds too risky, although I've had great luck at getting things to fit with a little spit in the past.
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on June 10, 2012, 02:16:50 AM
....lubricationnnn...
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 11, 2012, 01:13:40 AM
http://eshop.mainelyscooters.com/product/cat-139qmb/139qmb-gy6-hoca-idle-jet/ (http://eshop.mainelyscooters.com/product/cat-139qmb/139qmb-gy6-hoca-idle-jet/)

Does this look like the right fit?
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 11, 2012, 03:32:35 AM
That pict is actually a PWK type pilot. This is the one you need...
http://www.motorcyclecarbs.com/Keihin_Pilot_Jet_N424-25_C84.cfm (http://www.motorcyclecarbs.com/Keihin_Pilot_Jet_N424-25_C84.cfm)
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 11, 2012, 04:12:48 AM
Hmmm, That's not what I remember my pilot jet looking like at all, I'm pretty sure AG's all share the same carb though.... weird
Title: Re: When to upjet to a larger pilot jet
Post by: mono on June 11, 2012, 05:52:17 AM
The type Kenho21 found _looks_ the same as the ones in both my OEM carb and the chinese imitation carb that I own (although the main jets are different, the idle jets are interchangeable and the engine will run and idle, I tried)

The type that Zombie links to is completely different from what I've seen, it's way shorter....
Title: Re: When to upjet to a larger pilot jet
Post by: wordslinger on June 11, 2012, 10:34:16 PM
..kenho gots th' balll....

..z, take a trip to th sideline..you need a drink, bro!...lol..


                        :-*
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 12, 2012, 12:51:28 AM
The correct one is on that site, just not that exact site, its the n424-21 on the left menu bar. Kinda pricey from that site though, it was gonna be like 16 or 19 us for one jet, I emailed and asked if there was a way to avoid the $10 shipping charge. I ride a scooter, obviously not made of money hahaha
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 12, 2012, 02:38:35 AM
Obviously I got it wrong. I never open up the cv carb. Sorry Kenho! That is the same jet as a PWK carb tho.
I would just ask them to stick a stamp on it, and drop it in the post. 16 bucks is worth slapping them too.
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 12, 2012, 02:47:23 AM
Just ordered one from jetrrus.com for $13, got tired of waiting for email replies, that's the only bad thing about buying scooter parts online...dealing with the online part
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 12, 2012, 02:49:32 AM
I should have suggested buying an entire kit for 20 bucks. Sorry twice Dude...
Title: damnit
Post by: Kenho21 on June 12, 2012, 02:56:50 AM
Come to think of it that's my mistake, or lack of common sense. I saw em all over the place. $7 more for a set! Now I'm just upset with myself... maybe I can cancel the order
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 12, 2012, 02:59:27 AM
Yeah... I'd go suck on the barrel of a gun if it were me. Glad it's not tho... I have stuff to do tomorrow. Maybe Thursday tho.
Title: Re: When to upjet to a larger pilot jet
Post by: Kenho21 on June 12, 2012, 03:24:19 AM
Wow, maybe we should talk about that? lol My girlfriend is a counselor... We all love you and care about you a lot
Title: Re: When to upjet to a larger pilot jet
Post by: zombie on June 12, 2012, 03:27:10 AM
Ok... Maybe The Friday after next then. Damn people.
Love ya better.