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How to change Needle

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On my 01 250, I wanted to take a look and experiment with my needle. Well I had no idea how to take it off once I saw it. I had whole slide out. All I see on bottom is needle coming out, and on top is the cable going in. It's still stock.

I'm sure you guys know! Plus, what way I move it for rich and lean? thanks!!!

--mike;

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If you remove the cable you can get to the nut that holds the needle in place. Compress the spring down & move the cable to the side there is a slot on the nut that keeps the needle in place. If you move the needle clip up you go leaner & if you move it down you go richer. If your useing the stock mikuni carb it benefits by switching the s9 to an s8 nozzle. It will lean out the overall jetting.

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My bikes running Richer than Bill Gates. Well not that bad;; what this s8 and s9 thing you are talking about? I am about to change my main from a 420 to a 410 and see. It's mainly top end

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Pilot jet and air screw controls idel up to 1/4 throttle. You Needle controls 1/4 to 3/4 throttle and you'r Main jet is for 3/4 to wide open.

Write down where every thing at before you touch anything and for ever adjustment you make so you can return where you were if it don't work out same thing what jets you are changing to

Rule of thumb if you Air screw is less that .5 turns out you need a smaller pilot jet more than 2.5 to 3 turns out you need a larger pilot jet.

If you to rich on the needle drop down 1 clip leans it out at one slot at a time then take it for a spin do a plug reading each time with a new plug to see what the motor doing, brown good black rich, White very bad.

If the bike a constant throttle in mid range starts to ping rise the needle you to lean or you need to run more octain gas or change to a diffrent tapper needle one that more agressive taper in that are to get more fuel to the motor.

Raising the needle makes richer .

You rather be rich than to lean unless you like spend money to rebuild you lean siezed motor that you are now pushing back to the truck or home It gives you time to think what you just went and did and how much it going to cost you to get it running once again.

If you run wide open for long peroids of time use 1 size larger jet than you would normaly run if the temp out side drop to 20 degrees rejet you main the air thicker you need more fuel or you mite lean seize the motor.

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On my 01 250, I wanted to take a look and experiment with my needle. Well I had no idea how to take it off once I saw it. I had whole slide out. All I see on bottom is needle coming out, and on top is the cable going in. It's still stock.

I'm sure you guys know! Plus, what way I move it for rich and lean? thanks!!!

--mike;

The easiest way is to take your throttle apart so you have more play in your cable. You want to pull the spring out of the slide, but be careful not to stretch it. The spring is attached to a white plastic guide which sits on the bottom of the your slide. Once you have this out and out of the way, use a screwdriver or some sort of tool to push the cable out of the slot. You will need to allow the cable to go down some as it will not come out. Then use a 6mm and loosen that bolt. Done.

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Rule of thumb if you Air screw is less that .5 turns out you need a smaller pilot jet more than 2.5 to 3 turns out you need a larger pilot jet.

If you to rich on the needle drop down 1 clip leans it out at one slot at a time then take it for a spin do a plug reading each time with a new plug to see what the motor doing, brown good black rich, White very bad.

marv02, while the rest of your post is on the money, I think you got it mixed up with the air screw and pilot jet. If your air screw is less then 1/2 turn out, then you need a larger pilot jet, and if it's more then 3 turns out you need a smaller pilot jet.

The easiest way I've found to remove the throttle cable from the slide is to compress the spring/plastic sleeve with you fingers, then use a pair of needle nose pliers to clamp on the cable underneath the plastic sleeve to keep the spring compressed. Then you can easily remove the cable from the slide by moving it down and sliding it out the slot in the cable holder.

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Sorry Brain fart.:busted:

marv02, while the rest of your post is on the money, I think you got it mixed up with the air screw and pilot jet. If your air screw is less then 1/2 turn out, then you need a larger pilot jet, and if it's more then 3 turns out you need a smaller pilot jet.

The easiest way I've found to remove the throttle cable from the slide is to compress the spring/plastic sleeve with you fingers, then use a pair of needle nose pliers to clamp on the cable underneath the plastic sleeve to keep the spring compressed. Then you can easily remove the cable from the slide by moving it down and sliding it out the slot in the cable holder.

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