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ttr 125 running rough

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I need some help! 02 ttr 125 , just had the head bored 1 over and cut the top of the air box open,added bbr air filter. I also removed the end tail pipe and screen from the muffler. have been trying to rejet the stock carb. this bike was not running before this work. the jets i have been working with are 17.5, 20 idle and 105, 110, and 112.5 main. at idle to 1/4 turn the bike runs great high rpm's smooth. but at mid range it quits, and top it busts out? any ideas? I cleaned the carb but didnt soak it in any thing. it also smokes alot while running

Thanks: Hyperlite

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I have an xr70 that quit the more I held the throttle open, but that was caused by a air filter that was full of leaves, dirt, anything else on the ground/air. But if you just put a new filter in that wouldn't be the problem. Maybe the engine was put together incorrectly. Who intsalled the engine after it was bored?

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the rebuild shop bored and did the valve job, I put the engine back together. and set the timming, runs great at idle to 1/4 throtle, also adjusted needle twice.

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the rebuild shop bored and did the valve job, I put the engine back together. and set the timming, runs great at idle to 1/4 throtle, also adjusted needle twice.

Hmm, it'd be a lot better if I could see it in person. Maybe you should put up a vid of it. You personally put the engine back together? There's a chance you messed the timing or something else up.

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I have given the timming some thought but it runs great at idle to 1/4 throtle dont have rpm gauge but it revs all the way up at 1/4, and boggs at mid to top even when ridding

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I have a hunch that it is the timing or something similar. Not to be rude, but many people think they set the timing(or any other thing) correctly, but they didn't. Is this the first engine you've done?

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this is the first four stroke I have done. I'll check the timming again

Thanks for the help

I'll let ya know

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im no expert either but ive heard that if it sounds wet that it may be gettin to much gas causing it to bust out like that. it also may not be getting enough air flow to the filter,but i dont know if this is true or not.

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it bogs out on the needle bust out on the main

go down a couple sizes on the main and up one notch on the needle. Does it pop at all?

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cut the top off the air box and added bbr free flow filter getting plenty of air. to me that sounds like i need bigger jets, but it sounds wet like its flooding out? does this even with the stock jets?

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the BBR filter you have is a UNI filter. For some reason your bike is running rich. Did it do this before?

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not much popin at all I have tried 105 jet which was stock on this bike, I dont have any smaller main jets than that

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