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So i took it for its first 12 mile run, the first 12 that bike has seen. I let it warm up, just tooled around the neighborhood shortly, then ran some back country roads. It idled fine during warm up, but after getting back, just sitting there the idle seemed quite a bit higher then when it was warming up. Choke is in. I'm also guessing the funky smell is from the new engine and will eventually go away. Ideas?
 

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You are doing great so far nunya. It is not abnormal for idle to change a bit as engine breaks in, piston rings seal and bed into place. Same with funky smell as heat burns away dust and oils . btrnstfl (?) is correct, even if I can't figure out his handle, you can set the desired idle speed with adjustment on carburator side. And while out of convienience and habit we say "choke" the TW actually has an enrichenijg circuit rather than a choke. It ackomplishes same fuel mixture enrichment as a choke not by restricting airflow (choke) but rather by adding additional fuel to the airstream through carburator.
You are going to have fun with that new bike, nice you are concerned with proper break-in. And a big welcome!
 

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Btrnrsntfl = better than resentful? I'm sure I'm way off but that's one way I read it.

I think you are correct that the smells are because the engine is new.
 

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is it the one just low/right of the choke with a phillips head on the end? IF so, what exactly is being adjusted?
The idle speed screw holds the throttle open.
Turn it out and the throttle closes more, turn it in and the throttle can't shut as much.
 

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is it the one just low/right of the choke with a phillips head on the end? IF so, what exactly is being adjusted?
Yes. It may be normal for idle speed to increase a little as the engine breaks in. This knob is like turning the throttle to achieve your desires idle speed.
 

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You are doing great so far nunya. It is not abnormal for idle to change a bit as engine breaks in, piston rings seal and bed into place. Same with funky smell as heat burns away dust and oils . btrnstfl (?) is correct, even if I can't figure out his handle, you can set the desired idle speed with adjustment on carburator side. And while out of convienience and habit we say "choke" the TW actually has an enrichenijg circuit rather than a choke. It ackomplishes same fuel mixture enrichment as a choke not by restricting airflow (choke) but rather by adding additional fuel to the airstream through carburator.
You are going to have fun with that new bike, nice you are concerned with proper break-in. And a big welcome!

Bitter and resentful. Sounds like my ex-wife joined the forum;)


Tom
 
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So I understand correctly the idle should be high when hot? Just a got bike with 1500 miles on it. When cold it starts up and idles at 1300 RPM (I have a RPM gauge added) but when hot it idles at 2500-2700. I worry if I turn the idle down then when cold it will stall? Thanks for helping a newb!
 

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is it the one just low/right of the choke with a phillips head on the end? IF so, what exactly is being adjusted?
Note that the "idle adjustment" is not very accurate...what I mean to say is that (at least in my case...BOTH TW's) you can adjust it, but after a few minutes of riding, it will be either higher or lower than you set it.
I'm constantly fudging with it...and I think it has to do with the flexible cable/shaft thing on one side, that turns a screw on the other side of the carb. It retains a little bit of the torque that you impart to it, and as you ride...the vibration of the engine, releases the stored energy in the cable.
I might just take it out completely one of these days...
 

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Sounds like a lean running condition and/or a dirty low speed passageway or jet in the carburetor. Try some SEAFOAM in your gas first as this is the easiest fix if it can be corrected this way if dirty, especially if bike sat for sometime.

If the carb is clean. Still sounds like a lean running condition. Very common on these bikes from the factory to meet emissions as I have learned from this forum. Mine would idle high when hot and seemed to idle higher the hotter it got and would have extreme fluctuation of idle speed. Bike would also surge at constant speeds. Most notable at about 1/3 throttle or less, which is when the below mentioned low speed fuel circuit really does it's dance. Read on!

Some have been able to correct this condition by opening up the (predominately) low speed fuel mixture screw (covered by a factory plug) to 2 1/2 turns out from bottom. The factory setting is around 1 1/4 turns thereabouts. This (fuel) mixture screw meters (limits) the amount of fuel that the low speed/pilot jet in the bowl of the carburetor is capable of supplying the low speed fuel passageway just before it enters the intake manifold boot to the engine. Opening up this screw allows more fuel thus richening the fuel to air mixture. This helped my bike slightly but did not solve the problem. Not bored yet? Read on.

Once the fuel mixture screw is backed out to 2 1/2 to 3 turns, it is allowing the maximum amount of fuel that the tiny low speed/pilot jet can supply. In a lot of cases, especially at lower altitudes, this is still too lean a condition, such was the case with my bike that still had the factory #31 size low speed/pilot jet.

The real answer was to install a bigger, #34, low speed/pilot jet. Something also learned on this fantastic forum. If your carburetor is still factory spec'ed, and is clean, as mine was, most likely this will help yours as well.

If interested, and just adjusting the fuel mixture screw does not solve your problem completely, I would suggest only buying the part from YAMAHA as there has been some discussion about aftermarket parts not being the exact same size and fit.

YAMAHA PART # 5LB-14342-17-00 #34 Pilot Jet

This jet part number is only specific to 2001 and newer models with CV carb such as yours has if original. It is the best $10 improvement I have made to my bike.

Hope this helps,
Marty
 
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Sounds like a lean running condition and/or a dirty low speed passageway or jet in the carburetor. Try some SEAFOAM in your gas first as this is the easiest fix if it can be corrected this way if dirty, especially if bike sat for sometime.

If the carb is clean. Still sounds like a lean running condition. Very common on these bikes from the factory to meet emissions as I have learned from this forum. Mine would idle high when hot and seemed to idle higher the hotter it got and would have extreme fluctuation of idle speed. Bike would also surge at constant speeds. Most notable at about 1/3 throttle or less, which is when the below mentioned low speed fuel circuit really does it's dance. Read on!

Some have been able to correct this condition by opening up the (predominately) low speed fuel mixture screw (covered by a factory plug) to 2 1/2 turns out from bottom. The factory setting is around 1 1/4 turns thereabouts. This (fuel) mixture screw meters (limits) the amount of fuel that the low speed/pilot jet in the bowl of the carburetor is capable of supplying the low speed fuel passageway just before it enters the intake manifold boot to the engine. Opening up this screw allows more fuel thus richening the fuel to air mixture. This helped my bike slightly but did not solve the problem. Not bored yet? Read on.

Once the fuel mixture screw is backed out to 2 1/2 to 3 turns, it is allowing the maximum amount of fuel that the tiny low speed/pilot jet can supply. In a lot of cases, especially at lower altitudes, this is still too lean a condition, such was the case with my bike that still had the factory #31 size low speed/pilot jet.

The real answer was to install a bigger, #34, low speed/pilot jet. Something also learned on this fantastic forum. If your carburetor is still factory spec'ed, and is clean, as mine was, most likely this will help yours as well.

If interested, and just adjusting the fuel mixture screw does not solve your problem completely, I would suggest only buying the part from YAMAHA as there has been some discussion about aftermarket parts not being the exact same size and fit.

YAMAHA PART # 5LB-14342-17-00 #34 Pilot Jet

This jet part number is only specific to 2001 and newer models with CV carb such as yours has if original. It is the best $10 improvement I have made to my bike.

Hope this helps,
Marty
Very specific detailed report and even a part number... Love it brother Marty!! You are turning out to be a real asset to the forum, thank you bro!! (y)(y)(y)
 

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Very specific detailed report and even a part number... Love it brother Marty!! You are turning out to be a real asset to the forum, thank you bro!! (y)(y)(y)
Oh stop it, you're making me blush!

Thanks Tommy, but I must admit I probably just saved some of the others the boredom of answering this tried and true question that has been answered numerous times. That and, the problem of new member Subspd (Welcome To The Forum By The Way, please excuse my manners) of having to to do the Search and Rescue Mission Theme repeatedly to reach the Pathway of the Pioneers, such as yourself, who forged ahead before us, and charted the secrets of the universe that led to the discovery of the Holy Grail of T-Dub Ownership!

With Hat In Hand, I Humbly Thank You All ! !

Marty
 
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@Scooterbrained Thanks so much for helping a newb out! Guys like you are the key to great forums. 👍

I’m at sea level so your virtual diagnostic seems spot on. I’ll sea foam first but might just get the carb re-jetted eventually. Still trying to learn a lot! I did use the search which brought me to this old thread but having never owned anything other than a lawn mower with a carb it’s still Greek to me.
 

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@Scooterbrained Thanks so much for helping a newb out! Guys like you are the key to great forums. 👍

I’m at sea level so your virtual diagnostic seems spot on. I’ll sea foam first but might just get the carb re-jetted eventually. Still trying to learn a lot! I did use the search which brought me to this old thread but having never owned anything other than a lawn mower with a carb it’s still Greek to me.
You are welcome. Please note that the key here is to make only one change at a time to the carb to narrow down the problem. Some have changed low speed jet, main jet and adjusted the slide needle height all at the same time and still have issues without being able to eliminate the problem due several changes at once.

I was fortunate that the only issue I had was with the low speed circuit and the #34 pilot jet solved that completely. I had no problems with the medium speed settings (needle) and wide open speed (main jet).

While the low speed circuit is in play throughout the entire throttle range, causing the intermediate and high speed throttle to be a tad richer with the bigger pilot jet installed, it predominately affects/effects the idle and low speed range.

I would suggest to anyone with a lean issue of any kind/range to change only the pilot jet first as this is always the beginning of the throttle circuit. We Walk Before We Run! so to speak.

I think that if you change the pilot jet you will also notice the bike cranks a lot easier and often without choke when cold if the temp is not too low outside. This is a kindness that some of the rest of the bike's elements enjoys such as the starter and battery life. This follows course and makes it easier on the charging system to top off the battery quicker after start up.

From an abstract point of view, this also makes it easier and quicker to sneak away from the house before the Mrs. wakes up and points to the Honey Do Do List!!!! It is one of the secrets to the T.B.Y.S. success.

! ! "Take Back Your Saturday" ! !

Unless you are The Admiral; Whose Wife, Girl Friend and Best Friend, (she is one and the same) is probably pressing her own starter button before he does?????

Marty
 
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