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Discussion Starter #1 (Edited)
Hey guys,

I have I new TW ( love it ) . I know that everyone suggests re-jetting to 130 main which I will do. But I am also wondering if it would be a good idea to change the pilot jet since I ride at sea level.

If anyone has re-jetted at sea level, any tips/pointers would be greatly appreciated :)
 

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Discussion Starter #2
Where can I find a 130 main jet for the newer OEM mikuni carb. (2013 TW)

I would like to get the 130 b4 I continue any more of the break in process.
 

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My first choice for these parts will always be pure OEM from a dealer. As far as jetting for sea level I think there should be no difference from sea level right up to 3,000 feet above. Where I live is 1250 above and I can go in either direction to sea level or 3,000 above with no issue on jetting.
I will add one thing you have surely heard before, if it ain't broke don't fix it. While the bike is in warranty and break in if it is not properly adjusted for your geographic area then take it to the dealer and make him get it right.

GaryL
 

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Just my experience. I have a 2010 which I bought new over 2 years ago. Now have over 16,000 miles on sea level on it. Still haven't even touched the carb yet, meaning still have factory settings and have no issues. Same with my 2009, bought this Feb. also with factory settings and also no issues.
 

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I will add one thing you have surely heard before, if it ain't broke don't fix it.

GaryL
Good advice.

If the bike starts easily and runs good at all speeds, don't be so eager to make changes.

Maybe adjust the pilot screw, nothing more.

jb
 

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Good advice.

If the bike starts easily and runs good at all speeds, don't be so eager to make changes.

Maybe adjust the pilot screw, nothing more.

jb
Thanks jbfla. As you know and have been helping me through it, I am up to my ears in my own carb and quite deep into my check book trying to resolve my bikes issues. At this point I am quite sure my carb has some after market BS rebuild kit in it and no matter how clean I get it there is something that just does not gel at constant speeds right around 45-50. I have a big order in at Stadium Yamaha and am awaiting all the OEM individual parts. If after they arrive and the carb is back to pure stock it still does not perform correctly I also bought a brand new carb as back up. I rarely try to fix what is not broke but I am a complete lunatic about getting this bike to run as it should. I would go so far as to swap a known well tuned carb from a friends bike just to be sure mine will run right with it. I am pretty sure my problem is in the carb but well aware there could be some other electrical issue and all my efforts will be misguided. If my bike would run right I would out riding it instead of messing with it.

Another thing we have to be reminded of all the time is that just because one members bike runs great with particular jets and setting combinations does not mean you can copy it and get the same results. Carbs can be a finicky beast and all the stars and parts have to line up just right to achieve the best results. I ran a big dealership MC/ATV shop and there were a few carbs the mechanic worked on extensively and in the end he gave up and installed a new one because nothing he did fixed the problem and it certainly did not make for a satisfied customer until the machine did run right.

GaryL
 

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Discussion Starter #7
I have heard many ppl say that the TW runs much better with a bit more fuel. Just seems that if a bike at altitude runs better with more fuel, than one at sea level would benefit even more from a larger main jet. I have read a good number of posts concerning jetting, and every person that has commented on re-jetting with a larger main has had nothing but positive outcomes.

However I don't want to mess my carb up if they are so finicky that installing a new main jet will cause the bike to run poorly.
Even after I warm it up for a few mins it seems to sputter when I try to throttle up from idle in neutral, it gets past the sputtering after a few more minutes. But still the throttle does not seem to be as responsive as I think it should be. My friend has an older yamaha xs650 twin with 2 carbs and it starts up first kick when cold, and after 30 seconds he can blip the throttle and it revs right up.
 

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I too have read all those posts about larger jets being beneficial and I do agree there could be something to it. I bought the 118 jet and when I cleaned the carb and installed the new jet I found many non OEM parts in the carb. This is what I believe is causing my problems. Your carb may very well be just fine and run better with different jetting. You never mentioned any performance issue and instead said you have a brand new TW that I have to assume is under the warranty. Your dealer has an obligation to get a new machine running the way it should no matter where you live. I would have my bike back to the shop, explain the problem and let the mechanic test drive to feel the issue and then have them repair it. I would not take a chance of voiding my warranty by messing with a delicate carb or do any adjustments.
Consider this, you change the jets, you change the pilot setting and you blow your motor up. Any dealer will immediately refuse the repairs. I am on my own with my 22 year old bike and carb but you have a warranty and I highly suggest that you use it unless for some reason your warranty has expired.

GaryL
 

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You didn't mention the sputtering.

Yes, your carb is most certainly set lean on a new bike.

And turning out the pilot screw and putting in a slightly larger main jet (128 or 130) should help.

As GaryL said, give the dealer a chance to remedy the problem.

If you bring it to the dealer with the metal plug removed from pilot screw, and the bowl screws stripped, they will be reluctant to help without charging you.

jb
 

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New bikes are setup to run extremely lean in order to comply with federal/state emissions standards. I would be surprised if a dealer would adjust your carb to anything other than the original factory settings.
 

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New bikes are setup to run extremely lean in order to comply with federal/state emissions standards. I would be surprised if a dealer would adjust your carb to anything other than the original factory settings.
I would disagree with that dealer then Brian. A new bike from a dealer should not be sputtering and if it is then he better damn well fix it.

GaryL
 

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Discussion Starter #12
i appreciate all the input guys :)

i think i will do as you suggested and just adjust the pilot screw for now and see how it feels :)
 

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I don't know where to post! There is this wonderful conversation going on, and then you go start another thread here: http://tw200forum.com/forum/performance-customization/8122-130-main-jet.html Why? I'm confused. New bike, you're excited! Okay, I get it.

I ride around Puget Sound, and I imagine you are close by. So, here is my experience. First, ATV Parts, ATV Tires, Dirt Bike Parts, Motocross Gear, Motorcycle parts and Motorcycle Tires | Rocky Mountain ATV/MC is what you want for a lot of your OEM parts and other accessories. They are in Utah I believe. If their site says that it's in stock, you should have it here in two days. $7 flat rate shipping under $99 order, free over. Most dealers around here don't have anything in stock that I've looked for.

Next, you are talking carb tuning. Read the stickies on tuning and study that carb pictures one before taking your carb off and apart. Don't loose any of the small parts. I personally recommend stocking up on spare carb parts before you tear into it in case there is a mishap, or just to have on hand in your bike tool box for future use. I would include the bowl gasket, the pilot screw set (which includes the tiny oring and spring that are easy to loose), the needle valve set, and main jet #126, 128 & 130. (Part #'s 288-14355-63-00 = 126; 288-14355-64-00 = 128; 288-14343-65-00 = 130)

Your bike probably has a 126 in it. Mine did. For me, the 126 was too lean near sea-level, as were the rest of the stock carb settings. However, up in the mountains (4000' +) it was awesome. You can see my final carb settings in my signature, and here is how I got there. 126 to 128= noticable difference in all around performance with the bike. Butt-dyno says she pulls harder and is more fun. 128 to 130= very similar, but felt too rich to me, but better than the 126. Because it felt the best out of the three, because I do go to the mountains to ride, because it's probably slightly better gas mileage wise...the 128 is my jet. The needle definitely needs to come up, and the pilot screw needs to come out. Your butt-dyno, along with the carb tuning instructions, will tell you how much. For the needle, people seem to either use 0.010 shims or washers to raise it up. I went cheap and easy and got a couple of 2mm washers from Ace hardware. They mic'ed out at 0.022 for me. Finally, the screw. You'll need to get that metal cap off. Most just start a sheet metal or wood screw into the little hole and then grab the screw with some vise grip or something to pull it off. It takes a very narrow flat tip screwdriver to fit into the hole and adjust the pilot screw. I suggest getting a small driver like the orange handle ones that come with Stihl equipment. A dealer should have one for you cheap or free. and then cut off all but 1/2" of the handle. Then you'll have something to adjust with on the fly and when the carb is on the bike.

Last tip. The phillips head screws on the bike are not...they are JIS (Japanese Industrial Standard). A phillips screwdriver can easily strip them out. Use the screwdriver inside your onboard toolkit, or get yourself a set of jis drivers.

In case you aren't familiar with how our carbs work, this is very helpful visually:

 
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