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Discussion Starter #1
Just finished re-installing my carb with the ProCycle jet kit. I ended up using the 130 main jet, two shims and the supplied needle and idle jet. Started it up, its maybe 20 degrees or so here in Upstate NY, and ran awesome. The usual stuttering before its all warm and toasty was gone. I haven't had a chance to get on the road for a normal road test, but my question is, what should I be looking for or testing for to see if this is the right setup for my bike? I mean it doesn't smell to rich and runs strong, so is that just kind of it? If it isn't broke don't fix it maybe? Thanks Gents!
 

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If the idle is good and not wavering up and down and it doesn't hesitate with a good crack of the throttle, is warming up quicker and running smoother, you are probably close. See how it runs under a load in all gears and do a plug check to see if it is tan. (black would be too rich, whitish would be too lean) Have the engine running somewhere between midrange and highrange and pull in the clutch and kill the engine, then pull the plug and look.
 

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Discussion Starter #3
Will do, thanks for the plug check idea. A guy at work mentioned something about the possibility of burning up valves if you're not careful. That's why he said he always takes his carbs to shops. This has been my first go at any carb work but I mean its only a 200 designed almost 30 years ago... Seams like you would have to do something rash to kill this thing. Is that an actual possibility?
 

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Well, you haven't killed it yet, and with the tuning you have done, it should be safer from blowing up than it was...ha ha Do the plug check, it is important. As long as you are not too lean, you probably won't ever burn a valve on this bike. Ride on brother!
 

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The plug color test is the most informative and important test that a backyard mechanic has to tell what is happening inside the raging volcano of the engine when it is running.
 

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^^The "raging volcano of an engine that is called the TW" ^^ priceless.
 

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Brug, for me, changing the stock configurations of my carburator led to many seasons of fussing about to get it back to some improved middle ground.

Over the years, those that seem to have had lots of carb. experience have said over and over, carb. mods need to be done in a VERY METHODICAL MANNER.

It is not my intent to demean you in any way. Given my experience, and frustration, I had to chuckle at the wording, "fine carb tuning". I certainly hope that your 'fine tune' at 20 degrees will work as well at 70.

The TW certainly seems to be a 'cold blooded' machine. Playing with the idle jet adjustment is pretty straight forward and can make for faster 'start and go' opportunities. Jetting and shimming can be a whole nuther can of worms.

This is not so much for you, but for the others that may read your post and be inclined to think that twisting, shimming and changing jets is a slam-dunk process. For me, it was not. Yes, I got my 2006 to become rideable in cold weather a bit faster. However, like you, I went beyond the basic 'turn the jet in or out just a bit'. What I ended up having to deal with was this rather annoying 'hic-up/hesitation' around 3800 rpm. Now if you go through the gears fast, likely you are not close to 3800 rpm for more than a heartbeat. Should that be the case, my issue would not be noted by you. Given I ride off-road and slow, I am plus or minus 3800 rpm's a lot. My hic-up was certainly not a deal breaker, but still annoying.

Hope your changes work well for you under most temps and conditions. For those, like me, that would be inclined to think twisting a screw, installing a shim or changing a jet is close to a 'slam dunk' improvement, think again..

When Yamaha seeks out a middle ground for carb set-ups, likely the environment is temperature regulated, flow meters and emission sensors abound. The issue is not only air quality, but reliable/marketable performance.

If like me, you are inclined to make carb changes in a 'willy nilly' fashion, be prepared to 'chase your tail for some period of time.

Gerry
 

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Discussion Starter #8
Noted Gerry, as I was going through this project I was kind of thinking it may be best to only throw one variable in the mix at a time to really narrow down what does and does not work. That's kind of how I do things though, go balls out, find some sustains and some areas for improvements, then go balls out again. All part of living and learning I reckon. Thank you gentleman.
 

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My procycle jet kit instructions- for best performance, procycle recommends installing the #125 main jet, the #34 pilot jet, the enclosed jet needle, and one shim under the needle clip. this is a good starting point for tuning.
Stock #126 main-#31 pilot
 

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My procycle jet kit instructions- for best performance, procycle recommends installing the #125 main jet, the #34 pilot jet, the enclosed jet needle, and one shim under the needle clip. this is a good starting point for tuning.
Stock #126 main-#31 pilot
What exactly comes in this kit?? how jets and what sizes? my 2013 (all stock) takes for ever to warm up needs choke even on warm day. Slight ping on hills unless I use 91 or higher octain
 

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I prob shouldn't trespass here , don't even own a tw , but I do own a single two valve bike of a different color and make , but made in the same country .
the forum I lurk at has some very good carb guys , with that said .
the pilot and air screw control the bottom , slow to warm up , to lean . no choke needed , to rich .
the needle controls the broadest part of the fuel/air ratio , like 1200-6000ish.
and the main deals with the top 5000-10,000 rpms .
now that is not to say that they don't overlap some . but that is the basics

I've lurked here for a couple months . and the main seems to be the prob . when you hit the rev limiter your close on the main .

the float level is very important , that is first !!!!! that thing affects all the rest , if it's wrong , all else is for not .

all I got to say about that .
 

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Welcome Brug. This thread hit home because I lived in Hilton for 12 years up until 1996. 532 Parma Center road.

I can't add much more than you already have with your carb tuning though.

GaryL
 
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