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Surging at idle


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I am looking for a little help. I pulled my bike apart last year to powdercoat and polish everything. When I took the motor out, it ran great. I have just re-assembled the bike, and the only changes I made were switching from Stage IV pipes and stock CDI, to CPI in frames, and a Dyna. I bumped the main up from 152 to 155 (35PWK's) and left the needle and pilot where they were. I can not recall the needle position, but the pilot's are 58. It fired up on the third kick, and ran fine while warming up. Once warm it idles smooth for about 10 seconds, then drops down and runs rough for about 10 seconds, then back up to a smooth idle. If I let the bike sit, it will continue to do this. The timing of the up and down is consistant. Throttle response is fairly crisp (just running in the garage), but it does hang up for a few seconds after revving, before it settles down. I know that is typically a sign of lean, but I have not experienced the surging before. My thought was a float out of adjustment, but I checked them both, and they appear to be on the money.

 

Any thoughts?

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Maybe check carb boots for leaks.. Some people say to use wd40 and spray around.. If it boggs u found the leak.. Or just use carb spray witch is iffy but will make rev...ps just dont get it in eyes..lol
try it with a spray bottle and your premixed gas...

Also it could be the cdi... Stick your stock cdi back on and see if it fixes the problem... Lots of ppl have problems when they switch to an aftermarket cdi

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the DYNA cannot be anywhere close to the coil,.  you also need to run resistor plugs.   try bR8es or whatever your running now  just put the R in there  the dyna is a digital igniton and dosent take kindly to all that thar noise commin off o that thar coil n spurk pluuugs

 

ALSO check for air leaks.  the "hunting for idle" is common for a tad on the lean side..   BUT the dyna could be doing it also.  

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Lean was my original thought also, but as i browse through what others have for jetting with similar setups, my pilots at 58's seem to be high. Honestly, jetting is my weakest skill when it comes to tuning (and unfortunately probably the most important skill to have). I will fatten up this weekend, as see how it reacts.

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