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Discussion Starter #1
Was in the carport watching the rain come down.

Been thinking about the carb thing you all do. Remove that little cover to get to the screw you loosen two and a half turns.
Took off the side panels, and removed the gas tank. Hmmm. Sitting on my stool staring at the carb.

Looked pretty daunting. Finally removed the fuel hose and the other little hosey things.

I chickened out. BUT. I decided to try something other than removing the carb completely.

I went to the other side and removed the exhaust pipe. (I guess) Comes out the front and bends to the rear exhaust pipe. (?)

Next I was able to slide off a little electrical doodad at the brake switch.

Back to the other side I loosened the screws on the two rubber carb ends. One in front the other in back of carb.

Gently rotated carb so bottom came up on other (curb) side enough to get to bottom of carb. Sure enough it was covered. But I was able to give it a good tap with my ice pick. Hole was just enough
for me to screw in a long self tapping screw. Pried it out and voila! Access to the screw. Turned it in
and it was exactly 21/2 turns. Brought it out 3 turns and put it all back together.
The whole deal took less than an hour and I spent considerable time looking for my ice pick.

The rain finally stopped this evening and I did a test run. Guess what? I couldn't tell any difference ~GiGGle~

Sure this won't work on older bikes cause those rubbers probably dry out and get stuck to the carb or whatever. But it worked for me on my '13.

Now you all can come on here and say big deal. We all knew about that. Haha.
 

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Good for you! Maybe you should try shimming the needle tomorrow:rolleyes: Just kidding of course. Funny thing is my 2013 was exactly one turn out. My butt dyno made me think maybe I got just a touch better throttle response in the mid range but I swear the upper range of the throttle seemed to flatten a bit. May just need my butt dyno calibrated;) My bike does start MUCH easier than before and I often need no choke. I found the biggest difference was how much cooler my engine runs. Seriously my engine runs much, much cooler!


Tom
 
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Discussion Starter #3
Tom. It's so hot here (South Fl.) I don't think I can tell the dif. I will give it a long ride tomorrow.

Got to get my riding in before summer vacation is over and I have to meet my new class.
 

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Tom. It's so hot here (South Fl.) I don't think I can tell the dif. I will give it a long ride tomorrow.

Got to get my riding in before summer vacation is over and I have to meet my new class.
Good point about the stifling heat down that way. Up here however we have wild temperature swings and I rode on fathers day in 80 degree temps. My engine was cooler after 90 miles of mixed road riding than it was a month ago when I rode the same general route in 55 degree weather. It really is a BIG difference. My only regret was cooking my engine more than I needed to just to preserve a one year warranty:( Should have done that carb tweak on day one.

Tom
 
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Actually this technique has been posted here before, but good on you for figuring it out on your own.

Can I ask you why, if the bike was running fine, did you come out another half turn?
 
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When I opened mine to 2 1/2 turns (it was only open 1/2 turn before I started) it made a HUGE difference for the better. It went from barely running to an ultra reliable easy starting smooth running machine that was a pleasure to use.

I can understand why so many machines can be years old with just a few miles -- they run so crappy no one wants to ride them.
 

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Was in the carport watching the rain come down.

Been thinking about the carb thing you all do. Remove that little cover to get to the screw you loosen two and a half turns.
Took off the side panels, and removed the gas tank. Hmmm. Sitting on my stool staring at the carb.

Looked pretty daunting. Finally removed the fuel hose and the other little hosey things.

I chickened out. BUT. I decided to try something other than removing the carb completely.

I went to the other side and removed the exhaust pipe. (I guess) Comes out the front and bends to the rear exhaust pipe. (?)

Next I was able to slide off a little electrical doodad at the brake switch.

Back to the other side I loosened the screws on the two rubber carb ends. One in front the other in back of carb.

Gently rotated carb so bottom came up on other (curb) side enough to get to bottom of carb. Sure enough it was covered. But I was able to give it a good tap with my ice pick. Hole was just enough
for me to screw in a long self tapping screw. Pried it out and voila! Access to the screw. Turned it in
and it was exactly 21/2 turns. Brought it out 3 turns and put it all back together.
The whole deal took less than an hour and I spent considerable time looking for my ice pick.

The rain finally stopped this evening and I did a test run. Guess what? I couldn't tell any difference ~GiGGle~

Sure this won't work on older bikes cause those rubbers probably dry out and get stuck to the carb or whatever. But it worked for me on my '13.

Now you all can come on here and say big deal. We all knew about that. Haha.

I'm proud of you, you did alright. Try it and see how it goes. If it runs well or better, you did great. If it is hard to start, takes a long time to warm up, seems to run hot, needs the choke often to start it, it might need a little more adjustment. Keep us posted.
 

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What you did is an adjustment to the Pilot circuit. This is the air to fuel mixture ratio and determines if the bike runs lean or rich. Most bikes come from Yamaha adjusted rather lean so adding or richening them up a bit buy turning the pilot screw out a little is usually a good thing. The color of your spark plug end tells the most and you are looking for a tan color as opposed to black or white on the center porcelain part. You do not necessarily have to go with full half turns and instead it could be a very slight twist that brings it to just right. The only real adjustment is when the bike is fully warmed up and you can test it after each tiny twist to make sure it runs smooth all the way.

GaryL
 
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Discussion Starter #9
Actually this technique has been posted here before, but good on you for figuring it out on your own.

Can I ask you why, if the bike was running fine, did you come out another half turn?
Raining too much to ride. Also I tried Gary's (?) tailpipe finger test for carbon (?) and there was no carbon.

(Still is none~GiGGle~) Was afraid to go more than a half turn all at once. Next time I will try another half turn.
 

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Discussion Starter #10
What you did is an adjustment to the Pilot circuit. This is the air to fuel mixture ratio and determines if the bike runs lean or rich. Most bikes come from Yamaha adjusted rather lean so adding or richening them up a bit buy turning the pilot screw out a little is usually a good thing. The color of your spark plug end tells the most and you are looking for a tan color as opposed to black or white on the center porcelain part. You do not necessarily have to go with full half turns and instead it could be a very slight twist that brings it to just right. The only real adjustment is when the bike is fully warmed up and you can test it after each tiny twist to make sure it runs smooth all the way.

GaryL
Gary. Is it safe to infer there is another, better way to do this adjustment than what I did? I can't get a screw driver in there while it is hot.
 

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Gary. Is it safe to infer there is another, better way to do this adjustment than what I did? I can't get a screw driver in there while it is hot.
Find a cheap little screwdriver, cut off the blade about 2 inches long and use a small vise-grip to hold it and turn it. Grind or file it narrow enough to fit....you can do this when engine is cold so you can feel it seat in the slot. I've used this el cheapo method since day one five years ago because I've only adjusted the pilot screw twice in 11,000 miles. The first time when cold I closed it all the way GENTLY, and counted half turns to 2 turns out (for my altitude). Knowing that round number I could adjust a half turn easily. I never fussed with the more expensive tools. My engine seems fine from sea level to 10,000 feet with two turns out and a 126 main jet (2001 and up).

You should understand that the Pilot Circuit has VERY little effect above half throttle....the main jet takes over after that. It's mostly for tuning the idle and initial throttle response.
 

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Discussion Starter #12
Thanks Rocky. Based on that I think I am good at between 2 3/4 - 3 turns. Where I presently am.
 

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Gary. Is it safe to infer there is another, better way to do this adjustment than what I did? I can't get a screw driver in there while it is hot.
Sorry for the delay. There are lots of ways but I think what Rocky said will work. You are describing the burnt knuckle effect we all have felt when messing with this poorly placed adjusting screw.

Basically, once the pilot screw is set in the right position there is little need to keep messing with it. If the bike runs good, starts easy and is smooth from slow to top speed and your spark plug shows a light tan color then you are good to go.

We have a member here, Gregor, who makes extended pilot screws and sells them I think at the top of the classified section. These make this adjustment quick and simple. My bike ran great, started fine and had good acceleration but once I got to a steady 50-55 MPH I always felt an annoying buck or surge that bugged me. Adjusting the pilot screw to be just right cleared it up.

In your case, if it is running fine then just leave it. If not then make a tiny adjustment when the engine is cool, something in the line of an eight of a turn either way until you feel it is running better. If the porcelain part of you plug is very white then the carb is adjusted too lean. If it is dark and has oily burnt carbon then it is too rich, you want a light toast tan color on the plug.

GaryL
 

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I know I am running to rich. Spark plug says so (black & sooty). The bike starts fine every time runs at high rpm fine, but runs a little erratic at low throttle in low gears. Does this sound like a pilot screw adjustment would fix this?
 

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Discussion Starter #15 (Edited)
Only answering cause it's a thread I started. I know nada about carbs. But based on what I have gleaned from the guys on here that do know......I would say yes. Turn it in a bit. ~GiGGle~Out I meant. ~GiGGle~

I wish I could kill this. I have NO RIGHT to be giving mechanical advice~GiGGle~
 

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