30 miles to a tank ???

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Nickodemo
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30 miles to a tank ???

Post by Nickodemo »

2001 KDX 220R
New
piston/rings
rebuilt stock carb including jet block gasket
FMF narly pipe w brand new powercore 2 silencer
New crank/case /head seals
160 psi compression
needle 3rd position 38 /145 jets / float level set with kawasaki tool (glass gauge and tube) passes blow test
snorkel cut off
air screw and idle do do much. barely idles
I have done all of this in the last year trying to figure out why it runs rich and has low power. Its getting better but I still get 30-35 miles out of a full tank! Rode forest service roads last weekend and got 34 miles out of 2.9 gallons(full tank)
Thinking about selling out of frustration but I LOVE this bike! Any intell would be great
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Re: 30 miles to a tank ???

Post by KDXGarage »

Welcome to kdxrider.net. :bravo:
Thank you for participating on kdxrider.net. :bravo:
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Julien D
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Re: 30 miles to a tank ???

Post by Julien D »

Float height, maybe? How far can you lean the bike before it starts dripping from the overflow?
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John_S
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Re: 30 miles to a tank ???

Post by John_S »

Below is a post of mine from a while back...I would reset your float height manually.

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.
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Re: 30 miles to a tank ???

Post by John_S »

Get your bike warmed up and turn the air screw to 3 turns out. Rolling along in 1st gear at a walking pace, crank wide open throttle as fast as you can and let right back off. Just a split second. It works in neutral also but better with a load on the engine. Did it gurgle rich, lean bog like it was out of gas, or sound clean and start to pull the front wheel up? At 3 turns out it should lean bog. If it didn't then that's why its using so much gas. Hopefully you just need to reset the floats to 18mm and then start the jetting guide from the beginning. Either that or the needle jet is oblong which means the carb is worn out. Google "worn out needle jet" and click images.

When I work on my bike I use a clear gas tank that I made out of a bottle that hangs from the handlebars. A 1/2 turn or so on the air screw can take it from sipping gas at idle to visually guzzling gas at idle. If its rich enough it'll practically go through that bottle of gas like you opened the petcock and just let it drain out. I'm thinking that's the case with yours since the air screw and idle screw don't do much. Also try using genuine Keihin pilot jets if you're currently using aftermarket jets. I had a PWK 36 with a worn out needle jet that would guzzle gas at idle no matter what pilot jet / air screw setting I had.
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Re: 30 miles to a tank ???

Post by bufftester »

+1 on the above info. The fact that your AS and Idle adjust don't do anything certainly points at fuel delivery and the carb. My hybrid (2001 220 motor in a KX125 frame with a measly 1.9 gal tank) easily goes 50 + miles on a tank riding fairly hard.
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30 miles to a tank ???

Post by SS109 »

No KDX should ever get that bad MPG.

Another for float height. You're probably losing fuel while riding and it's running rich (hence poor idle/no air screw tunability) due to a high float level. Don't follow the spec in the manual. Set it at 18mm and report back.
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Nickodemo
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Re: 30 miles to a tank ???

Post by Nickodemo »

Going riding today. I will try the test after readjusting float level! Thanks for the help. On another note ... there is a brand new Keihien 35mm PWK air striker I can buy for $100. Should I buy it?
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Re: 30 miles to a tank ???

Post by rungrandpa »

I was dealing with low MPG issue this summer. Adjusting float height improved my MPG from 12 to 20.
Adjusting float height for me was a trial and error project. After trying different levels I ended up setting it slightly over 16mm.
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Re: 30 miles to a tank ???

Post by KDXGarage »

On the $100 carb, is it a Chinese counterfeit?
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Re: 30 miles to a tank ???

Post by rungrandpa »

I've been jetting my 1990 200 and I've achieved 22 mpg regularly, while riding pretty fast. I have settled on a 40 pilot, 1174 needle on second notch, and 155 main. I think reducing the pilot jet from 45 helped my MPG. I went down as low as 38, but picked up a bog.
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