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what is jetting?

By Rickstarr,
in Honda 2 Stroke

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Experienced

Michael N

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I am by no means an expert on jetting... quite the opposite. As far as i know... to "re jet" you carb is to adjust the jets or replace them with different sizes/settings to restrict or maximize flows of fuel/air. Until you get the mixture just right to the bike is running perfectly for the conditions you ride.

For example if you move from living at sea level to 2000 feet above you would need to re-jet your bike for the air you ride in (thinner air) since you are higher.

Hope i didn't just make all that up and it is true

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scalejockey

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I am by no means an expert on jetting... quite the opposite. As far as i know... to "re jet" you carb is to adjust the jets or replace them with different sizes/settings to restrict or maximize flows of fuel/air. Until you get the mixture just right to the bike is running perfectly for the conditions you ride.

For example if you move from living at sea level to 2000 feet above you would need to re-jet your bike for the air you ride in (thinner air) since you are higher.

Hope i didn't just make all that up and it is true

:eek: That about sums it up!
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Huffa 2

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Most bikes from the factory come jetted on the rich side simply because a lean running engine can over heat much easier and shorten the lifespan quite a bit or even seize the motor if they are too lean.

A lean motor will have a drier looking plug but it gets real technical what circuit (main jet, slow jet, needle, air screw) the motor is running lean on unless you do plug chop test which means you run the motor (riding the machine) at a certain RPM for a bit then pull in the clutch and kill the motor coasting to a stop.

The plug must be clean (AIR FILTER TOO !!) or better yet a new SP to start out with and once you read the plug, you can tell at that precise RPM if it's lean or not and decide what circut it is running on.

i'm no jet expert either so anyone feel free to correct me if I'm wrong about something.

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Huffa 2

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The last two new bikes I bought ('06 XR650L & '06 XR650R) both came jetted extremely lean. I think it was due to Honda's environmental kick they are on. The 650L was so lean that when it warmed up, it was next to impossible to start.

True, the 650's really need help, mine still is a bit lean even with a jet kit in, I may try a larger main with richning the fuel screw up a bit.

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Huffa 2

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thanks for the info everyone!

i will have my motor completely rebuilt very soon assuming i dont **** anything up and i'll be flying around local tracks like a bat out of hell in no time :applause:

:eek: Once you get the jetting right ?

........come to think of it, I'm quite sure I have tests (MX Action & Dirt Bike) on the 97, I saved all tests on 7,8&9 since I had a 98 and they were all pretty much the same.

Interested in reading any ?

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Rickstarr

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:eek: Once you get the jetting right ?

........come to think of it, I'm quite sure I have tests (MX Action & Dirt Bike) on the 97, I saved all tests on 7,8&9 since I had a 98 and they were all pretty much the same.

Interested in reading any ?

yes :applause:

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