Heres some help for poor low end preformance

Discussion specific to the 1995 - 2006 KDX200 (H Series) and 1995 - 2005 KDX220R (A Series) models sold in the USA
bikeman2502001
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Re: Heres some help for poor low end preformance

Post by bikeman2502001 » 06:03 am Nov 16 2020

Here is a little better summery of the gas mileage difference I used to be able t ride 30 miles per tank Now I am able to ride 40 miles and have almost 2 quarts left Im pretty happy now thats acceptable and it runs awesome too boot

MoonStomper
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Re: Source and part #?

Post by MoonStomper » 12:42 pm Nov 16 2020

I noticed some wear on my slide when I recently installed a fresh kit. Mine runs pretty good, but always a little grumbly/less sharp off idle.
This sounds like worth a try... Where is the best place ya'll have found to source this slide? Part number?
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Rocks, roots and STOOOPID speed on two-wheels - what could possibly go wrong?!?
'03 KDX 200 - 50+C Hare Scramble Bike @%@ '18 Trek Slash 8 - 50+ Masters Enduro Race Bike

BLACKSBURG, VIRGINIA USA

bikeman2502001
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Re: Heres some help for poor low end preformance

Post by bikeman2502001 » 09:29 pm Nov 16 2020

Sudco carburetor akways has all the carb parts you will ever need. I found mine on ebay there about 60 bucks. Please read the entire post here as the needle position is very different i have the sea level figured out for you should be good to 4000 feet or so the carburetor will be completely reprogramed
You will be grinning ear to ear. Smile

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Re: Heres some help for poor low end preformance

Post by MoonStomper » 11:20 am Nov 17 2020

QUESTIONS:
My H9 is still running the OEM pipe & OEM #5 slide (snorkle removed)...
Will this new #7 slide make the same improvements if still running the OEM pipe?
~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~
Rocks, roots and STOOOPID speed on two-wheels - what could possibly go wrong?!?
'03 KDX 200 - 50+C Hare Scramble Bike @%@ '18 Trek Slash 8 - 50+ Masters Enduro Race Bike

BLACKSBURG, VIRGINIA USA

bikeman2502001
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Re: Heres some help for poor low end preformance

Post by bikeman2502001 » 05:29 pm Nov 19 2020

Yes this cleans up all the jetting issues at the low end we all suffered from this in not just a high performance mod it will make any bike run alot better and now i can see it will pay for it self in gasoline savings a win win Any 2 stroke i ever buy that has a 5 in it will be changed before i even ride it i consider it a must have in my book.
To any one trying this at higher elevations remember if your bike bogs off idle in low end you need to raise the needle until it goes away the old ways of tuning doesnt apply anymore

bikeman2502001
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Re: Heres some help for poor low end preformance

Post by bikeman2502001 » 10:57 pm Jan 01 2021

I have a cold weather update here now that some good air finally got to the south even i breath noticeably easier my bike went lean on me so bad it ran on in extended high rpm use and was bogging off idle. Even though my plug was picture perfect and my silencer was chalky coffey with cream i was very lean Not a big problem just needed to adjust a couple of things, remember if your bike is bogging off idle it is the pilot and needle position with the 7 slide. I am now at
45 pilot
Stock needle bottom 5th position
165 main
Air screw 1 turn out
Sea level 50 degrees
Also i believe it is a good idea to change the needle those of you with rb carbs could share your needle with us would be great i have purchased a Ktm needle for a 13 250 xcw for 10 dollars N8RJ as it uses a 36 mm carb abd a 7 slide as mine is after mod i havent installed it yet but it should give me even richer adjustments available when temps go down from here . I still believe now more than ever that this is the biggest mod to the rb carb not the divider as it has been an awesome mod much cleaner off of the bottom and noticeably better mileage at a total carb price of 160 good luck!

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Re: Heres some help for poor low end preformance

Post by KDXGarage » 03:47 am Jan 02 2021

CEK has been mentioned a lot over the years
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128

MoonStomper
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Re: Heres some help for poor low end preformance

Post by MoonStomper » 08:52 am Jan 04 2021

bikeman2502001 wrote:
10:57 pm Jan 01 2021
I have a cold weather update here now that some good air finally got to the south even i breath noticeably easier my bike went lean on me so bad it ran on in extended high rpm use and was bogging off idle. Even though my plug was picture perfect and my silencer was chalky coffey with cream i was very lean Not a big problem just needed to adjust a couple of things, remember if your bike is bogging off idle it is the pilot and needle position with the 7 slide. I am now at
45 pilot
Stock needle bottom 5th position
165 main
Air screw 1 turn out
Sea level 50 degrees
Also i believe it is a good idea to change the needle those of you with rb carbs could share your needle with us would be great i have purchased a Ktm needle for a 13 250 xcw for 10 dollars N8RJ as it uses a 36 mm carb abd a 7 slide as mine is after mod i havent installed it yet but it should give me even richer adjustments available when temps go down from here . I still believe now more than ever that this is the biggest mod to the rb carb not the divider as it has been an awesome mod much cleaner off of the bottom and noticeably better mileage at a total carb price of 160 good luck!
Bikeman...
You say "165" main and 45 pilot. That's richer than the 155 main for the #7 slide and less lean by one size on the pilot I saw recommended before (42 pilot/155 main/OEM needle). If you tried that (previously recommended) set up, what did you notice about it that caused you to change?

Regarding the needles. Do I understand correctly that the OEM needle has more abrupt transitions as the throttle increases where the CEK needle is leaner than OEM on the bottom with a more subtle change as throttle is added? Actually, after studying this chart... https://jetsrus.com/a_jets_by_carbureto ... 27-48.html
I realize that I need to find out what the OEM needle actually is (where I'm starting from) and where it falls on the chart - or rough equivalent - in order to know which direction I'm going. Does anyone know the code for the OEM needle (H9 model)? Is it the 1173, which is like a CEP?

KDXGarage...
Where do you purchase your needles, JetsRUs?
~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~^~
Rocks, roots and STOOOPID speed on two-wheels - what could possibly go wrong?!?
'03 KDX 200 - 50+C Hare Scramble Bike @%@ '18 Trek Slash 8 - 50+ Masters Enduro Race Bike

BLACKSBURG, VIRGINIA USA

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Re: Heres some help for poor low end preformance

Post by KDXGarage » 01:47 pm Jan 04 2021

I haven't purchased in a long time, but sudco or jetsrus are the two places that many have had success with.
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128

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Re: Heres some help for poor low end preformance

Post by kdxdazz » 04:13 pm Jan 08 2021

1173 is a beq equivalent
1999 KDX220SR (KDX220-B5)

kdxdazz
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Re: Heres some help for poor low end preformance

Post by kdxdazz » 04:13 pm Jan 08 2021

Sorry I meant the 1174 is beq equivalent
1999 KDX220SR (KDX220-B5)

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