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Discussion Starter #1
So I got some shim washers from Mcmaster/carr as recommended from the carb tune posting. Also I got a #130 jet. I live at just above sea level. So I installed 4 .001 washers and the 130 jet. The bike started off fine until I came to a hill. Then it wouldnt rev up above idle. I had to pull the choke all the way on to get it home. So then I removed the needle shims and left in the 130 jet. Same problem. So the I put back in the stock 126 jet and 3 shims. Now she works great! I can feel a bit more pull and she runs great.



So I have the stock exhaust.

removed the softer snorkle thing from the airbox.

no other modificatios.

I did not drill out the idle hole thing??



So can anyone tell me why the 130 jet would not work out? Is it because my exhaust is too restrictive? I am hopin to learn something here1



 

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What you describe is not a jetting issue. Sounds more like a fuel supply issue. Take your needle to the hardware store and get a $0.05 flat washer instead of expensive "shims".
 

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Discussion Starter #6
I double checked the shim size and they are indeed .010. my typo. 7$ is cheap to me!!



I dont know what was in the jar. the dewd in the photo is not me, but my friend Ed. So basically, I want what was in the jar too!!



Qwerty, with the 130 jet and 4 shims then more fuel should be going in right?? But it would only run smooth with the choke on. Then with 126 jet and 3 shims its great. Am I understanding this wrong because that seems a bit back asswords? Educate me.....



who wants to rock?

 

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Yes it does sound back asswards.



EDIT: I didn't read your first post properly.



So I'll try again, with the 130 jet and 4 shims was the spark plug black, wet, dry or what, If the small jet works better it sounds like you went too rich but if you had to use the choke it sounds like it was weak. Back asswards indeed. You will have to find out whether it was rich or weak also it was a Yamaha TK jet was it.

I assume you have a CV (later model carb)



Your mates look like a lot of fun.
 

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Discussion Starter #9
Got the jet at my local yamaha dealer and it is round head. I dont have a part number though I could dig it up if necassary. So I am not sure who specifically manufactured it. I have yet to view the spark plug. It runs great now. I just got back from running some errands on the bike and it is the best it has been so far. I am not really trying to find a bunch of power here, I know it is only 196cc. I got a WR250 that has tons of frikn power. Ridding that Sunday at Lake Wenatchee. Anyways, thanks for all the replies and help guys...





YM
 

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Your #130 didn't cause your ride quality problem, especially since it seems the bike ran fine until you reached the hill, than ran so lean it would only run with the choke on. You either have a defective jet, it sucked trash into the hole just as you reached the hill, or something else was preventing fuel to reach the engine. Better figure it out ASAP before you get stranded in a bad place.
 

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Discussion Starter #12
What I did was put back in the stock jet #126 (hex head) and used three .010 shim washers on the needle. Now it works beautifully. Went back to the afore mentioned hill and she pulled up it real nice, better than before. So as of now the only change from stock in my carb (TK) is the three .010 washers on the needle.
 

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I would try the 130 again. Or at least pull your 126 and compare it to the 130 and see any noticeable differences in inlet diameters and head heights (too tall on the 130 could mean it's too close to the float bowl and preventing full flow. Put the 130 back in and if the symptoms repeat, it's the jet. It could have been a fluke piece of debris that got in the needle/seat area, then when you switched back to the stock jet the debris got cleaned out.



I would try it again. Gotta find out if it's repeatable.
 

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I live at about 200 ft above sea level and just put in a 130 and 3 x .01 washers. Gonna put a fourth in and see how that does. Feels pretty close to stock now... pulls a little stronger around midrange though. Still fiddling with it.
 

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maybe try checkin the air filter, it could be full of crud. proper air/fuel ratio is very important. that i learned from a hard luck experience! im about 325 feet or so above sea level and i run a #130 with two .020 shims with an DG slip on exhaust.
 

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Discussion Starter #16
Hey thanks a lot guys I think I will check the height of the jet. I dod not turn my air/fuel screw at all during this. The jet being to close to the bottom of the bowl makes the most sense to me so far. So when I am done with my frikn math im hoping to get into the garage!! Thanks again all for the help.



DG slip on exhaust eh??? hows that? how much louder is it?
 
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