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Carb tuning help

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Well my sons are growing up and I recently bough a TTR 125L for the oldest. It's a 05 very clean all stock.  I was lurking here and read pages and pages of infoicon1.png on the carb. I ordered the 17.5 pilot and 110 main. Started first kick after the jet install. I have the pilot/fuel screw at about 1 3/4 turns out. My question is about getting a steady idle.

 

Problem: Warm it up and come to a stop on level ground, sometimes the idle will slowly speed up. Or if you lean it to the left the idle speeds up. Lean it to the right no change at all stays runnig normal. You can blip the throttle sometimes and it does not come back to a slow idle, it slows but not back to a putaput putt. You can tap the kill switch a few times an it comes down to a nice idle. ??? Do i not have the piloticon1.png/fuel screw right? Float?

 

Now the weird thing is my other son'sicon1.png xr70 does exactly the same thing. What ever I do they both do exactly the same thing. Both carbs were dissasembled and ultrasonic cleaned.

 

Before I put in the new jets, the ttr was hard to start cold and to keep it runningicon1.png I had the pilot/fuel screw about 3 truns out and the idle almost all the way in.

 

 

Thanks

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I would be verifying that the float levels are set to correct spec. firstly.

Running on after closing the throttle indicates lean.

Did you have the fuel screw removed when you had the carbs cleaned? If not, then that passage got ommitted and its critical for proper running.

3 turns out on the fuel screw is the max you want to come out with it. If its still running too lean, then you need to go to the next size larger pilot jet and retune the fuel screw.

Make sure you have no air leaks around the carb boots or between the front boot and cylinder.

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I would be verifying that the float levels are set to correct spec. firstly.

Running on after closing the throttle indicates lean.

Did you have the fuel screw removed when you had the carbs cleaned? If not, then that passage got ommitted and its critical for proper running.

3 turns out on the fuel screw is the max you want to come out with it. If its still running too lean, then you need to go to the next size larger pilot jet and retune the fuel screw.

Make sure you have no air leaks around the carb boots or between the front boot and cylinder.

 

I completley dissassembled the whole thing. All passages are open. When we got the TTR the fuel screw was 1.5 out. It took like 3 out and idle screw almost all the way in to run. After the re-jet I figgured it would be rich so I went to 1 3/4 as a starting place. I'm hoping with just a few more small tweeks it will smooth out and idle nice.

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