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New TTR125, jetting questions

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My girlfriend bought a brand new 2017 TTR125 earlier this year.  We are looking to get a little better performance out of it.  I've taken the snorkel out and opened up the airbox a little bit.  I have not cracked open the carburetor yet.  I've read the "everything you need to know about your TTR125" sticky.  I was planning on removing the metal screen in the airbox.    

Can anyone tell me what the stock jetting is on the carburetor?  We live at 7500 feet in CO and most of our riding is at 8000 feet and above.  I'm thinking I need to change out the pilot jet to a leaner one, and maybe also change the main jet to a leaner jet.  Can anyone who lives at similar altitude give me your jetting specs?    

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That bike doesn't have any more power hidden inside of it. Your best enjoyment is to get it running properly, and then they are terrific bikes.

The stock pilot is a 15, and I use a 17.5 or a 20 even at high altitude.  It makes such a huge difference in how it starts and idles. The factory main jet, which I measured at nearly 18-1 A/F mixture in Denver on a dyno, will be ok for up high. It was super lean at sea level to keep the EPA and California happy.

Removing the metal screen won't do anything noticeable.  The bike makes 7.97 HP, and no more with a pipe. When it is too slow for the rider, the Kawi KLX 140 or Honda CRF150F is the next step up, followed by the TTR 230.

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Thanks, I appreciate your response.  I'm gonna change out that pilot jet.  Hopefully that does the trick.  

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Does it start and idle???  Does it stumble from bottom to the top???  Also, it's going to be down on power due to the elevation. A BBR kit would help power wise.

 

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On 8/18/2017 at 4:39 PM, socalxr said:

Does it start and idle???  Does it stumble from bottom to the top???  Also, it's going to be down on power due to the elevation. A BBR kit would help power wise.

 

It starts and idles fine.  Sometimes the idle seems bit low, especially when the bike is cold.  It doesn't stumble from bottom to top, but it doesn't seem to have any power on the bottom end.  That's where I was looking to get a little better performance, in 1st and 2nd gear.  

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As long as it starts, idles, and revs good, jetting is fine.  At 7500', it's going to be down on power, and with a 7hp bike it's going to feel pretty slow in stock form.  A BBR filter kit, carb, lightened flywheel, pipe, and BBK will make it much better.  

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So just to follow up-I pulled apart the carb and the main jet was a 100, pilot was a 15.  The pilot jet was totally clogged, couldn't even see through it.   Must have gotten some bad gas somewhere along the way.  I cleaned out the pilot jet and it's running a heck of a lot better.  

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It usually won't even start, yet alone idle with a plugged pilot.  I'm glad you said, "see though it".  So many people soak it or spray a cleaner though it, but never actually hold it up to a light to see though it. 90% of the time, if a running bike (on mini-bikes), suddenly doesn't start or something, it's the pilot.  They get plugged easy.  Glad you got it going.  

Edited by socalxr
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