carb needles wanted to buy

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kdxdazz
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carb needles wanted to buy

Post by kdxdazz »

hi guys, i have a kdx220 with RB"d carb and the CEK needle i have in it is just too rich,currently using a cheap chinese needle that i have soldered the straight diameter to get me by,i am looking to buy any keihin needles that are leaner than a CEK and especially interested to try the OEM kdx needles. i live in thailand so buying any needle here is just not an option,obviously would be looking for you to post to thailand. PM me what you have and costs please,don't even know where the messages are on this website so my email is evilcaneval77@hotmail.com also facebook by the same email
1999 KDX220SR (KDX220-B5)
John_S
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Re: carb needles wanted to buy

Post by John_S »

Have you tried setting your float height to 18mm? A lot of people on here have experienced the "too rich" pilots and needles (myself included) with the floats set at 16mm. I had a CEL and other needles that I couldn't get to work and the pilot was a 35. I changed the floats to 18mm and it changed everything. Then I could run a 40 pilot and the CEL on the second clip and the air screw adjustments worked as you would expect.

How much is it roughly to send an envelope from the US to Thailand?
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carb needles wanted to buy

Post by pumpguy »

[How much is it roughly to send an envelope from the US to Thailand?[/quote]


A phone call to your local post office should provide an answer to this question.
kdxdazz
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Re: carb needles wanted to buy

Post by kdxdazz »

i have tried everything a man should do to a PWK carb. i have the float level set at 19mm, oring gasket replaced,i even welded a bung into the expansion chamber and put in my wideband O2 sensor. with the CEK needle it runs 11.5-1 at idle and thats with a 32 pilot jet,with the soldered up needle i am at 14-1 at idle which is good for a 2 stroke but there are many inconsistencies throughout the rev range as i just put it in a drill and sanded it to get the profile. i also have a drz400 and i spent 2 years following jetting reccomendations on thumpertalk only to work out every single person was wrong,unless you have spent time jetting bikes close to the equator and at altitude its just not what you think it would be.
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Boxfresh25
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Re: carb needles wanted to buy

Post by Boxfresh25 »

kdxdazz wrote:i have tried everything a man should do to a PWK carb. i have the float level set at 19mm, oring gasket replaced,i even welded a bung into the expansion chamber and put in my wideband O2 sensor. with the CEK needle it runs 11.5-1 at idle and thats with a 32 pilot jet,with the soldered up needle i am at 14-1 at idle which is good for a 2 stroke but there are many inconsistencies throughout the rev range as i just put it in a drill and sanded it to get the profile. i also have a drz400 and i spent 2 years following jetting reccomendations on thumpertalk only to work out every single person was wrong,unless you have spent time jetting bikes close to the equator and at altitude its just not what you think it would be.
Can you tell us what kind of issues you are having with the bike besides you think it's rich? I have a 220 that did not run right when I purchased it and really through me for a loop. I have been a master technician for 25 years I rebuild and restore old 2 stroke motorcycles and have been to many efi classes and have masters from multiple efi universities and have been doing custom tuning for 15 years as it's one of my passions. All this experience and training the 220 still had me messed up lol.

I'm not sure what kind of problems you are having but for me it was the horrible 4 stroking very blubbery feeling at cruise. I spent all kinds of money trying to tune it out jets needles boxes and boxes of plugs you name it. I got pretty close with the stock carb and had it running dam good but it was far from perfect and no further tuning could be done without leaning it out more than I was comfortable with, Like you leaner I went the closer it was. I ended up getting a brand new RB carb and the difference was dramatic in the running and tunability but it was still not perfect. The final fix and number one mod I would recommend to anyone with a 220 is the head mod as the 220 compression ratio is not good especially if you ride on the street like me.

As far as tuning by AFR You need to give the engine what it needs not what you think it needs or what someone one on the internet tells you it needs. You can't tune 2 strokes with a wideband, you can but there are two many variables like engine design, fuel mixture, scavenging, spooge, contaminations in general that will cause bad data and quickly ruin your wideband. You tune by reading plugs and doing plug chops if you don't trust your plug chop data you can check your cylinder wash with a borescope . These are your eyes and ears into the engine. Once that is complete and correct you can put on your wideband (in the proper location) and check you AFR for reference and fine tune from there.

Please don't lean your engine out anymore All though I don't believe in tuning 2 strokes by AFR they run way richer than 4 strokes. We are talking about a KDX not a racing cart or drag racing snowmobile two completely different beasts.

AFR reference for 2T:
Idle 8:1-10:1
Low Speed 10:1-13:1
Light Load (Lean Cruise) 14:1-16:1
WOT 12:1-13:1
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Re: carb needles wanted to buy

Post by kdxdazz »

appreciate the response, not sure what i can add except for proof of how rich it is running, with the CEK needle and a 32 pilot jet it will not idle even with the fuel screw turned out 4 turns, the soldered needle is much better but still not great as the measurements are very inconsistent, it runs so rich it has thick grey smoke coming out of it, now i live in a city of a million people so when i am at the traffic lights people avoid me and hold there nose,quite embarrassing, the temperature here is about 35 degrees celsius and 80-90 percent humidity, i live at 600 metres above sea level at 1000 metres it will not idle and at 2000 metres it just runs plain awful, my friend has a brand spanking new ktm300 and his runs so rich it fowls plugs often.

i think you may have made a typo with the idle AFR , only a methanol engine would run at 8:1. my bike seems to run smoothest at idle at 15:1

i have never really understood why people keep choosing the CEK needle as the needle of choice,as i understand it the standard needle is closer to BGQ with a very rich pilot jet,people complain already that this is a way rich set up,kawasaki did this so when the bike is shipped to other countries its as simple as leaning out the pilot,with the CEK there is no room for leaning it out.

the head on my bike has already been machined by rob black although i am not sure why you say this makes a difference to how rich it runs but i still have a lot to learn so could well be

i still have not done a leak down test and that will be done in the next couple of weeks

even though the bike runs rich right through the rev range i would be happy if i could just get it to run well at idle so i don't have to keep blipping the throttle to keep the engine running
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Boxfresh25
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Re: carb needles wanted to buy

Post by Boxfresh25 »

You would not run a methanol engine at 8:1 tuning in lambda will make the transition between different fuels much easier. AFR for methanol is is a little different 6.4:1 = 1.00 lambda. stoichiometric AFR for gasoline is 14.7 so on gasoline 14.7 = 1 lambda. Methanol idles around 0.90-0.95 lambda (5.76 :1- 6.08 :1) but since methanol is more for racing and not idle cruise so full power would be .75-.80 lambda (4.80 :1- 5.12 :1) for a NA engine.

it's not a typo if your going to use a incorrect tool to tune a 2T carbureted dirt bike don't expect to get the same numbers you would from a 4 stroke efi especially at idle. There are so many variables to get a clean afr reading at idle on a 2 stroke don't even bother, heck even with efi it's so unstable we have sensors that look at the afr, throttle, map and have a crap ton of correction tables that make instant corrections to the fueling table to maintain the commanded afr at and off idle.

Glad to hear you have the head mod done already. My comments on that in my post was more about my personal experience as I was not quite sure of your exact issue at the time but I'm gathering it's just idle specific. The head mod will have no meaningful effect on idle afr.

How did the bike run before the RB carb mod? New carb, old carb, if old carb did you clean before and after?

If it was my bike and even know the carb was an RB. I would inspect the jet block gasket for proper installation.

I have a new BGQ needle if you think that's what you need I don't think it will have any effect on your idle issue but it's your if you pay the shipping. Pretty sure I have a jet block gasket too.
Last edited by Boxfresh25 on 10:49 am Jul 28 2018, edited 2 times in total.
kdxdazz
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Re: carb needles wanted to buy

Post by kdxdazz »

Cheers thank you. I would like to try the BGQ. The bike had the rb mod done when I bought it, the previous owner couldn't get it running right so sold it cheap, when I bought it,it had about the same power as my scooter,was hard to believe but true,im going to keep looking for a standard carb as I have no need for top end power,everything I do is single track, are you able to contact me on Facebook please . Any help appreciated as parts here in Thailand are non existent and jetsrus won't accept non USA PayPal accounts
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Re: carb needles wanted to buy

Post by SS109 »

kdxdazz wrote:...as I have no need for top end power,everything I do is single track...
Just a heads up on the RB modified carb, it helps bottom end just as much as it helps top end. The Rb carb gives the KDX a wider power range compared to a standard PWK carb.

I personally think you really need to do a leak down test to make sure the engine seals are good. On the jets you have been using, are they genuine Keihin or an off brand?
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Re: carb needles wanted to buy

Post by John_S »

I had the same issue with a Keihin PE34. It wouldn't idle and smoked like a mosquito fogger. The PE has a replaceable needle jet. That $9 part made a huge difference and instantly idled and had predictable air screw tuning. A PWK does not have a replaceable needle jet. I have a PWK 36 that won't tune because the needle jet is worn out.

Google "worn out needle jet" and click images. Look down through the top of your carb into the emulsion tube (where the needle enters) with a magnifying glass. If yours is oblong like in those pictures there isn't a needle on the market that's going to help.

Edit: good point above SS109. I ran non genuine pilot jets and it was worthless to try and tune. Extremely unpredictable one size to the next. I second the leak down test so you know what you're dealing with.
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Re: carb needles wanted to buy

Post by Boxfresh25 »

kdxdazz wrote:Cheers thank you. I would like to try the BGQ. The bike had the rb mod done when I bought it, the previous owner couldn't get it running right so sold it cheap, when I bought it,it had about the same power as my scooter,was hard to believe but true,im going to keep looking for a standard carb as I have no need for top end power,everything I do is single track, are you able to contact me on Facebook please . Any help appreciated as parts here in Thailand are non existent and jetsrus won't accept non USA PayPal accounts
I can't find you on facebook by that email.

John_S made an excellent point about the needle jet being worn especially since when your manipulating the needle thickness with solder and its leaning out your idle. Unfortunately the needle jet is not replaceable your carb, you would require a new carb or possibly a good used jet block could be sourced. I have all of this.

First thing first do the leak down. Then check the needle jet and make sure the hole is perfectly round and not egg shaped. A good way to check is by removing the jet block so you can get a better look then use the reverse side (round side) of a drill bit and find the largest one that slides through the needle jet, as you move the reverse side of the drill bit in and out you will be able to tell rather quickly with the naked eye if the hole is perfectly round or not.
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carb needles wanted to buy

Post by kdxdazz »

Good points on the needle jet/emulsion tube,i did check it but not with the drill bit idea so it's got me thinking it might be worn and coupled with the CEK needle it's just too much gas. I will check it again as soon as I can and I am trying to put together a leak down tester made from an old blood pressure testing unit.
I was using non genuine keihin jets , I also thought they might not be sized properly so went out and bought genuine jets but nothing changed.
Boxfresh I can definitely be found on Facebook by that email,my name on Facebook is Darryl glen . I'm interested in the parts that you have as I don't have the funds to buy a new carb and anything imported new here in Thailand is subject to import taxes. Would still like to try the BGQ needle as even if everything was brand new I still think the CEK will be still rich at 4000 feet and 35 degrees Celsius
I've even experimented with different fuels as I know through my wideband testing they give very different AFR readings. On 100 percent gasoline it will barely run as it is so rich and runs much better and leaner on e10.
Thanks for the input guys
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carb needles wanted to buy

Post by kdxdazz »

Forgot to say I have a theory that it's not the crank seals as when I turn the fuel tap off and keep riding it there is a period of about 5-15 seconds where the idle goes very high and the bike runs really well
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carb needles wanted to buy

Post by KDXGarage »

kdxdazz wrote:Forgot to say I have a theory that it's not the crank seals as when I turn the fuel tap off and keep riding it there is a period of about 5-15 seconds where the idle goes very high and the bike runs really well
I think they all do that. My 87 did that back in '87 when I would go to a friend's house then forget to turn the gas back on before going home. ZOOOM!!!
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