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Jetting for high compression piston

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Installed a wiseco 14.1 high compression piston into a 2009 kx250f with 16.5 hours on it. Valves are good, timing is good, new spark plug,carb is clean, rung straight VP U-4 with R&D fuel excelerator. When rev'ed bike has a pop to it on the release of the throttle. When it is ridden there is no power on bottom. First gear feels like your taking off in third . Could anyone recommend jetting info. My guess is that it's running lean, but that's only a guess.

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If you were running pump fuel before....try going up 2 sizes on the main & pilot.

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I will stop by the shop and get both jets in the next to sizes up. I will update later tonight on the results, thanks.

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So I went from stock jetting to two steps bigger on the main and pilot. That took the pooping out but still have nothing on bottom. And I mean nothing! First gear feels like 3 when taking off. The bike almost has a muffle sound to it. When the motor is rev'ed it seems to die down quick.

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The bike sounds great now, but I think I might have figured it out. I think I messed up by tightening the timing chain to tight and it's putting the motor under a load of pressure and advancing the timing a little bit causing it to have no power when taking off. First gear feels like I'm taking off in 3rd. I thought the timing chain was not tight enough when I put the chain tensioner on so I stuck a screw driver in and gave it one or to more clicks to tighten it up. I will find out when I get home. WHat do you think?

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