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01 yz426 tuning issue

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Hi all first time posting here, i did a search and can't find my topic. I just got a 01 yz426f that wouldn't start and idle. I took the bowl off and cleaned the carb passages and jets and bowl, replaced the pilot jet with a new standard 42. Also while off took the time to do the bk mod i found on this site have that set to about .35 sec to the best of my ability. Bike starts good and idles nice, have the fuel screw at 1.5 out and from idle with a quick crack of throttle it sputters/bogs. Did the same thing before i timed the AP. Any help would be much appreciated. Also 900-1000 Ft altitude, 75-85 deg F, 50-60% humidity. Seems like it only really happens noticebly while on the stand trying to get it tuned, when im test riding around the neighborhood it only happens a couple of times the rest of the time its trying to throw me off on the ground lol

I have also sprayed around carb and boots and no sign of an air leak, and check valve clearances since its new to me.

Edited by Yrider93
Forgot some important info

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Anyone? this has got me stumped and bugging the crap out of me. I think its gotta be the accel pump but i don't know where to go from where im at.

 

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Could be the a/p pump, check to make sure it is still intact.  The FCR carbs are kind of notorious for having a low end bog.  My 450 does it too.  Seems like the Boyesen Quick Shot is the best cure.

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It is a brand new diaphragm. Yea i have definitely seen that the bog is common on the site. Starting to wonder if im just being way to picky but i want the power now lol and if im not careful it will stall the bike when it occurs

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