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Doing my first Carb rebuild on my 87. Got to the needle portion and am looking for help on what to disassemble first Their is a spring in the center. If I slide the pin out and release the tention on the spring, I have no idea how I would reattach it. Seams like there must be a better way. Youtube only has one video and the Carb looks different on his 88 model. Any help appreciated
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20200812_190757.jpg
 

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Actually there is no real need to remove the slide/needle but if you want to first remove the screw on the left (in your picture) and that will disconnect the "arm" going to the slide from the shaft that is spring returned. Then with a thin screw driver remove the two screws deep inside the slide. You should be able to swing the arm thing to the left and the slide will come out.

But as I said before, it is a lot simpler just to leave it all together and spray it with carb. cleaner. It can be a little frustrating putting it back together.
 

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Some pics that might help.

The two screws I was referring to. Picture only shows one screw but I tired to draw black arrows showing where they go.
Carb spring 2 screws.jpg

A plastic thing and spring you must not let get lost. (Needle in picture is junk! Didn't work at all.)
Carb spring 2.jpg

Picture of carb with slide removed and swing arm swung to the left.
PICT2569.JPG

Since you have it all apart I hope you are installing a BRAND NEW #114 high speed jet. I have said it so many times before but it really makes a huge difference. A new #40 pilot jet is also highly recommended.
 

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I was thinking about my experience with needle replacements. As a general rule, at least for me, compare the stock with the replacement. If they are not similar in taper and the same length I have found (for me) it has led to nothing but trouble as in running overly rich.

The needle with the different clip positions came in a carb kit that ended up being useless. The other needle is a stock one and was reused.
PICT2564.JPG
P5190027.JPG
 

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Some pics that might help.

The two screws I was referring to. Picture only shows one screw but I tired to draw black arrows showing where they go.
View attachment 207458

A plastic thing and spring you must not let get lost. (Needle in picture is junk! Didn't work at all.)
View attachment 207459

Picture of carb with slide removed and swing arm swung to the left.
View attachment 207460

Since you have it all apart I hope you are installing a BRAND NEW #114 high speed jet. I have said it so many times before but it really makes a huge difference. A new #40 pilot jet is also highly recommended.
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There is a video on YouTube called yamaha tw needle shim mod , I used this as a help when I was doing carb mods on my tdub.
My advice is whilst you have carb off to fully strip it and replace any suspect parts on it!! With genuine yamaha parts
my bike only had less than 2 k miles on it and it ran crap and hot due to weak mixture , I tried all air screw turn outs etc , worked up to a point , but found that the carb was bleeding in air from the choke mechanism and the fuel cut off diaphragm , as diaphragm was weak on side where the little rubber pipe attaches .
I shimmed a new needle as per video for midrange hesitation ( trial / error set up mind ) I also replaced stock #114 main with #116 the #118 made no difference to top end speed the pilot #040 was also changed to a #42 off a xt 350 , no need for choke unless its really cold and the tick over is amazing now and eng temp a lot cooler, a thing to check is float height they will hesitate a bit if that float bowl is not full especially on full throttle , and also renewed fuel needle and seat, basically everything renewed except the barrel slide which is no longer sold so I was informed when I did carb a few years ago , I still get good mpg on standard gearing and my fat ass on it also
 
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